A device, system and method for establishing a biological tissue frostbite model and evaluating frostbite degree

Abstract

This invention discloses a device, system, and method for establishing biological tissue frostbite models and evaluating the severity of frostbite, belonging to the field of biomedical technology. The technical problem this invention aims to solve is the lack of real-time, quantitative methods for evaluating the severity of frostbite in existing technologies. To address this problem, the device provided by this invention includes a sample stage, a spray cooling system, an infrared thermal imager, a laser speckle blood flow imaging system, and a control system. The control system, based on the temperature monitored by the infrared thermal imager, controls the spray cooling system to execute a preset cooling strategy to establish models of different frostbite degrees, and simultaneously collects temperature and blood flow data for subsequent analysis. This invention achieves accurate establishment of frostbite models through the spray cooling system, utilizes the laser speckle blood flow imaging system for non-invasive, real-time monitoring of blood flow changes in the frostbite area, and uses the relative rate of change in blood flow as a quantitative indicator for evaluating the severity of frostbite, thus realizing an objective, real-time, and non-invasive evaluation of the severity of frostbite.

Description

Technical Field

[0001] This invention proposes a device, system, and method for establishing a biological tissue frostbite model and evaluating the degree of frostbite, belonging to the field of biotechnology. Background Technology

[0002] Frostbite is localized tissue damage caused by exposure to extremely cold environments, and its severity is closely related to the freezing temperature and duration. In medical research and preclinical experiments, establishing standardized animal frostbite models is fundamental for exploring the pathological mechanisms of frostbite and evaluating treatment options. Currently, frostbite models are mainly established using contact freezing, where a pre-cooled metal probe is directly attached to the animal's skin or ear, and different degrees of tissue damage are achieved by controlling the temperature of the freezing probe and the contact time. In assessing the severity of frostbite, traditional methods primarily rely on visual observation of macroscopic morphological changes in the damaged area, such as redness, swelling, blisters, and the extent of necrosis, combined with histopathological section analysis for final grading. In addition, infrared thermography is also used to monitor the surface temperature distribution of the frostbitten area to help determine the damage boundaries.

[0003] However, existing technologies have significant limitations in establishing frostbite models and assessing their severity. In model establishment, contact freezing methods struggle to precisely control the cooling rate and freeze-thaw process within tissues, resulting in poor model repeatability. In severity assessment, visual observation is highly subjective and cannot provide quantitative evaluation; while histopathological analysis is the "gold standard," it requires tissue sectioning, is invasive, and cannot provide dynamic, continuous monitoring of the same injury site. Infrared thermography only provides surface temperature information and cannot directly reflect the microcirculatory state of deeper tissues, yet circulatory disturbances are a core element in the pathological evolution of frostbite. Therefore, the current lack of a real-time, non-invasive, and quantitative technique for assessing frostbite severity makes it difficult to meet the practical needs for dynamic monitoring and precise grading in frostbite mechanism research and clinical treatment. Summary of the Invention

[0004] This invention provides a device, system, and method for establishing a biological tissue frostbite model and evaluating the degree of frostbite, which solves the technical problem that the existing technology lacks real-time, non-invasive, and quantitative means to evaluate the degree of frostbite, making it difficult to meet the actual needs for dynamic monitoring and accurate grading in frostbite mechanism research and clinical treatment.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: In a first aspect, this application provides a device for establishing a biological tissue frostbite model and evaluating the degree of frostbite, comprising: Sample stage, used to hold biological tissue samples; A spray cooling system, with its nozzles facing the sample stage, is used to spray and cool the biological tissue sample to establish a frostbite model; An infrared thermal imager, whose field of view covers the biological tissue sample, is used to monitor the surface temperature of the biological tissue sample in real time. A laser speckle blood flow imaging system, with an imaging field covering the biological tissue sample, is used for non-invasive, real-time monitoring of blood flow changes in the frostbitten area of ​​the biological tissue sample; and The control system is connected to the spray cooling system, the infrared thermal imager, and the laser speckle blood flow imaging system, respectively, and the control system is configured as follows: Based on the temperature monitored by the infrared thermal imager, the spray cooling system is controlled to execute a preset cooling strategy to create a biological tissue frostbite model with a predetermined degree of frostbite. The temperature data monitored by the infrared thermal imager and the blood flow data monitored by the laser speckle blood flow imaging system are collected and stored simultaneously for subsequent frostbite severity analysis.

[0006] As a further improvement to this application, the spray cooling system includes: Refrigerant receiver tank, used to store refrigerant; A pressurization unit, connected to the refrigerant storage tank, is used to pressurize the refrigerant in the refrigerant storage tank; A nozzle, connected to the outlet of the refrigerant reservoir via a pipe, is used to spray pressurized refrigerant onto the surface of the biological tissue sample; At least one solenoid valve is disposed on the pipeline between the refrigerant receiver and the nozzle, and connected to the control system, for controlling the on / off state of refrigerant injection; and At least one pressure sensor is disposed in the refrigerant reservoir and / or the pressurization unit and connected to the control system for monitoring pressure.

[0007] As a further improvement of this application, the control system is also configured to: control the pressurization unit to pressurize the refrigerant storage tank when the pressure of the refrigerant storage tank is lower than a first preset threshold, based on the pressure monitored by the pressure sensor; and output a prompt signal to replace or replenish the pressurization medium when the pressure of the pressurization unit is lower than a second preset threshold.

[0008] As a further improvement to this application, the control system is configured to execute the preset cooling strategy, including: Based on the temperature data monitored by the infrared thermal imager, identify the moment when the surface temperature of the biological tissue sample drops to 0°C; The timer starts from that moment and continues until the preset frostbite duration is reached; When the preset frostbite duration is reached, the spray cooling system is controlled to stop cooling.

[0009] As a further improvement to this application, the control system is also configured as follows: Within a first preset time after the spray cooling system stops cooling, the infrared thermal imager and the laser speckle blood flow imaging system are controlled to continue to synchronously acquire data; After the first preset time, the infrared thermal imager is controlled to stop acquiring data, and the laser speckle blood flow imaging system is controlled to intermittently acquire data at preset time intervals for a second preset time.

[0010] As a further improvement to this application, the control system is also configured as follows: Based on the collected blood flow data, the relative rate of change in blood flow before and after frostbite was calculated; the formula for the relative rate of change in blood flow is: BFI before BFI is used to measure the blood flow velocity of frostbitten samples before cooling. after The blood flow velocity of the sample 3 days after frostbite.

[0011] As a further improvement of this application, the control system is also configured to: generate a temperature change curve of the surface of the biological tissue sample based on the temperature data monitored by the infrared thermal imager; and generate a blood flow distribution map and / or blood flow change curve of the frostbite area based on the blood flow data monitored by the laser speckle blood flow imaging system.

[0012] Secondly, this application provides a system for establishing a biological tissue frostbite model and evaluating the degree of frostbite, characterized in that it includes: The aforementioned device; and A pathological analysis device is used to perform pathological analysis on biological tissue samples processed by the device to determine the degree of frostbite as the gold standard.

[0013] Thirdly, this application provides a method for establishing a biological tissue frostbite model and evaluating the degree of frostbite using the aforementioned device, comprising the following steps: Step S1: Sample fixation, fixing the biological tissue sample onto the sample stage; Step S2: System focusing, start and adjust the infrared thermal imager and laser speckle blood flow imaging system to focus on the surface of the biological tissue sample; Step S3: Model establishment. The spray cooling system is activated through the control system to spray and cool the biological tissue sample according to the preset cooling strategy in order to establish a frostbite model. Step S4: Data acquisition. During and after the model building process, the control system synchronously acquires and stores the temperature data monitored by the infrared thermal imager and the blood flow data monitored by the laser speckle blood flow imaging system. Step S5: Data analysis. Based on the collected blood flow data, calculate the physiological parameters used to characterize the degree of frostbite.

[0014] As a further improvement to this application, step S6 is also included: establishing evaluation criteria, performing pathological analysis on biological tissue samples that have undergone different preset cooling strategies to obtain the gold standard for their degree of frostbite; and performing correlation analysis between the relative change rate of blood flow and the gold standard for the degree of frostbite to establish a relationship or threshold for evaluating the degree of frostbite.

[0015] The advantages of this invention over the prior art are as follows: This application provides an apparatus, system, and method that integrates frostbite model establishment and frostbite severity assessment. First, precise control of the frostbite process is achieved through a spray cooling system combined with real-time temperature monitoring by an infrared thermal imager. Specifically, the control system accurately identifies the moment when the tissue surface temperature drops to 0°C based on temperature data fed back from the infrared thermal imager, using this as the starting point for frostbite timing. By controlling the cooling duration, frostbite models of different severity are established. This temperature feedback-based closed-loop control method significantly improves the standardization and repeatability of frostbite model establishment, overcoming the shortcomings of low control accuracy and poor model consistency in traditional contact freezing methods.

[0016] Secondly, this application introduces a laser speckle blood flow imaging system, enabling non-invasive, real-time, and dynamic monitoring of blood perfusion in frostbite areas. Changes in blood flow are a core physiological indicator reflecting the degree of tissue damage and the repair process. Compared to the subjectivity of visual observation and the invasiveness of pathological sections, laser speckle blood flow imaging technology allows for long-term, continuous monitoring of the same injury site, obtaining objective and quantitative blood flow data. By calculating the relative rate of change in blood flow before and after frostbite, this application elevates the evaluation of frostbite severity from qualitative description to quantitative analysis.

[0017] Finally, this application establishes a quantitative relationship between the relative rate of change of blood flow and the "gold standard" degree of frostbite determined by pathological analysis. This means that in subsequent applications, only the relative rate of change of blood flow needs to be monitored using a laser speckle blood flow imaging system to achieve an accurate, non-invasive, and rapid assessment of the degree of frostbite in biological tissues, eliminating the need for invasive pathological sampling. This technical solution fills the gap in existing technologies regarding the lack of real-time, quantitative methods for evaluating frostbite, providing strong technical support for research on the pathological mechanisms of frostbite, evaluation of drug efficacy, and clinical treatment decisions. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following description is provided with accompanying drawings of the relevant technical solutions in the embodiments of the present invention or the prior art. It should be understood that the accompanying drawings described below are only for the convenience of clearly illustrating some embodiments of the technical solutions of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 Schematic diagram of a system for creating frostbite models and evaluating the severity of frostbite; Figure 2 Steps for creating a frostbite model and evaluating the severity of frostbite; Figure 3 Surface temperature and blood flow distribution diagram; Figure 4 Blood flow change curve; Figure 5 Blood flow variation curves under different spray parameters. Detailed Implementation

[0020] The embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. The step numbers in the following embodiments are set only for ease of explanation, and there is no limitation on the order between the steps. The execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0021] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0022] The first objective of this invention is to provide a device for establishing a biological tissue frostbite model and evaluating the degree of frostbite, comprising: Sample stage, used to hold biological tissue samples; A spray cooling system, with its nozzles facing the sample stage, is used to spray and cool the biological tissue sample to establish a frostbite model; An infrared thermal imager, whose field of view covers the biological tissue sample, is used to monitor the surface temperature of the biological tissue sample in real time. A laser speckle blood flow imaging system, with an imaging field covering the biological tissue sample, is used for non-invasive, real-time monitoring of blood flow changes in the frostbitten area of ​​the biological tissue sample; and The control system is connected to the spray cooling system, the infrared thermal imager, and the laser speckle blood flow imaging system, respectively, and the control system is configured as follows: Based on the temperature monitored by the infrared thermal imager, the spray cooling system is controlled to execute a preset cooling strategy to create a biological tissue frostbite model with a predetermined degree of frostbite. The temperature data monitored by the infrared thermal imager and the blood flow data monitored by the laser speckle blood flow imaging system are collected and stored simultaneously for subsequent frostbite severity analysis.

[0023] The control system precisely controls the execution of spray cooling based on temperature feedback from the infrared thermal imager, while simultaneously acquiring temperature and blood flow data. This achieves precision and standardization in establishing frostbite models, overcoming the arbitrariness of traditional methods; it enables simultaneous, non-invasive monitoring of the two key physiological parameters, temperature and blood flow, during the frostbite process and subsequent recovery; and it lays a data foundation for establishing a quantitative relationship between "blood flow changes and frostbite severity," fundamentally solving the problem that existing technologies cannot provide real-time, quantitative evaluation of frostbite severity.

[0024] Furthermore, the spray cooling system includes: Refrigerant receiver tank, used to store refrigerant; A pressurization unit, connected to the refrigerant storage tank, is used to pressurize the refrigerant in the refrigerant storage tank; A nozzle, connected to the outlet of the refrigerant reservoir via a pipe, is used to spray pressurized refrigerant onto the surface of the biological tissue sample; At least one solenoid valve is disposed on the pipeline between the refrigerant receiver and the nozzle, and connected to the control system, for controlling the on / off state of refrigerant injection; and At least one pressure sensor is disposed in the refrigerant reservoir and / or the pressurization unit and connected to the control system for monitoring pressure.

[0025] Through pressure sensor monitoring and solenoid valve control, the refrigerant can be injected at a stable pressure and flow rate, thereby ensuring consistent cooling conditions for each frostbite model and further improving the model's repeatability.

[0026] Furthermore, the control system is also configured to: based on the pressure monitored by the pressure sensor, when the pressure of the refrigerant reservoir is lower than a first preset threshold, control the pressurization unit to pressurize the refrigerant reservoir; when the pressure of the pressurization unit is lower than a second preset threshold, output a prompt signal to replace or replenish the pressurization medium.

[0027] The system monitors the pressure in the storage tank and pressurization unit in real time, automatically intervening or alerting the operator when the pressure is insufficient. This feature significantly improves the automation level and operational reliability of the device. Automatic pressure replenishment ensures continuous and stable injection pressure during long-term or multi-round experiments; low-pressure alarms prevent unexpected pressure drops during experiments due to gas depletion, thus preventing experimental failures or model inconsistencies and ensuring the continuity of the experimental process.

[0028] Specifically, the control system is configured to execute the preset cooling strategy, including: Based on the temperature data monitored by the infrared thermal imager, identify the moment when the surface temperature of the biological tissue sample drops to 0°C; The timer starts from that moment and continues until the preset frostbite duration is reached; When the preset frostbite duration is reached, the spray cooling system is controlled to stop cooling.

[0029] The starting point for frostbite timing is set at 0°C (360°F). The control system reads temperature data from the infrared thermal imager in real time, identifies the 0°C moment, and begins timing, automatically stopping after the preset frostbite duration is reached. This is the core technology for achieving accurate frostbite modeling. Initial temperatures may differ between individuals and different body parts. If the timing starts at the beginning of spraying, the actual effective frostbite time (the time the tissue is below freezing) will be inconsistent. By using 0°C as the starting point, individual differences in the cooling phase are eliminated, ensuring that the degree of frostbite is determined solely by the "time the tissue is frozen," greatly improving the model's scientific rigor and repeatability.

[0030] Furthermore, the control system is also configured to: Within a first preset time after the spray cooling system stops cooling, the infrared thermal imager and the laser speckle blood flow imaging system are controlled to continue to synchronously acquire data; After the first preset time, the infrared thermal imager is controlled to stop acquiring data, and the laser speckle blood flow imaging system is controlled to intermittently acquire data at preset time intervals for a second preset time.

[0031] The data acquisition strategy after frostbite is divided into two phases: high-frequency synchronous acquisition is performed within a preset time period (e.g., 5 minutes) after cooling stops; then, a long-term intermittent acquisition mode is entered (e.g., acquisition every hour for 3 days), during which the infrared thermal imager is shut down, and only the laser speckle blood flow imaging system is used. This phased acquisition strategy balances data comprehensiveness and resource efficiency. Short-term continuous acquisition can capture rapid physiological changes in the early stage of rewarming (e.g., reactive hyperemia); long-term intermittent acquisition is used to track the long-term evolution and repair process of microcirculation after frostbite. At the same time, turning off the infrared thermal imager in the later stage reduces unnecessary data volume and equipment power consumption, making monitoring more targeted.

[0032] Specifically, the first preset time is 5 minutes, the second preset time is 3 days, and the preset time interval is 1 hour.

[0033] The first preset time was set at 5 minutes, the second preset time at 3 days, and the data collection interval at 1 hour. 5 minutes was sufficient to observe the dramatic changes in the early stages of rewarming; 3 days is a typical time point when frostbite damage tends to stabilize; and the 1-hour interval achieved a good balance between capturing long-term trends and avoiding data redundancy. This provided clear guidance for subsequent implementation.

[0035] The control system is configured to calculate the relative rate of change of blood flow using the following formula: BFI before BFI is used to measure the blood flow velocity of frostbitten samples before cooling. after The blood flow velocity of the sample is 3 days after frostbite.

[0036] The third preset time point is the third day after the frostbite model is established.

[0037] Furthermore, the control system is also configured to: generate a temperature change curve on the surface of the biological tissue sample based on the temperature data monitored by the infrared thermal imager; and generate a blood flow distribution map and / or blood flow change curve of the frostbite area based on the blood flow data monitored by the laser speckle blood flow imaging system. Transforming raw data into visualized charts has the following advantages: 1) It facilitates researchers' intuitive understanding of the dynamic evolution of the frostbite process; 2) It provides a basis for subsequent analysis, such as allowing precise selection of regions of interest from the blood flow distribution map for quantitative calculations; 3) It enhances the presentability of the technical solution, and these charts serve as strong evidence of the technical effectiveness in academic exchanges or clinical trials.

[0038] Secondly, the present invention provides a system for establishing a biological tissue frostbite model and evaluating the degree of frostbite, characterized in that it includes: The aforementioned apparatus; and A pathological analysis device is used to perform pathological analysis on biological tissue samples processed by the device to determine the degree of frostbite as the gold standard.

[0039] The pathological analysis equipment is used to prepare and analyze the biological tissue sample slices.

[0040] Thirdly, the present invention provides a method for establishing a biological tissue frostbite model and evaluating the degree of frostbite using the aforementioned device, comprising the following steps: Step S1: Sample fixation, fixing the biological tissue sample onto the sample stage; Step S2: System focusing, start and adjust the infrared thermal imager and laser speckle blood flow imaging system to focus on the surface of the biological tissue sample; Step S3: Model establishment. The spray cooling system is activated through the control system to spray and cool the biological tissue sample according to the preset cooling strategy in order to establish a frostbite model. Step S4: Data acquisition. During and after the model building process, the control system synchronously acquires and stores the temperature data monitored by the infrared thermal imager and the blood flow data monitored by the laser speckle blood flow imaging system. Step S5: Data analysis. Based on the collected blood flow data, calculate the physiological parameters used to characterize the degree of frostbite.

[0041] It also includes step S6: establishing evaluation criteria, performing pathological analysis on biological tissue samples that have undergone different preset cooling strategies to obtain the gold standard for their frostbite degree; and performing correlation analysis between the relative change rate of blood flow and the gold standard for frostbite degree to establish a relationship or threshold for evaluating the degree of frostbite.

[0042] The biological tissue sample is the ear or skin of a live rabbit, or the ear or skin of a live rat. The nozzle is an adjustable nozzle used to adjust the distance and / or spray angle between itself and the biological tissue sample on the sample stage. The refrigerant used in the spray cooling system is medical cooling spray or liquid nitrogen. The control system is also used to adjust the spray pressure or spray pulse width of the spray cooling system in real time based on the temperature data monitored by the infrared thermal imager, in order to control the cooling rate of the surface of the biological tissue sample.

[0043] This invention combines a laser speckle blood flow imager, an infrared thermal imager, and a refrigerant spray cooling system to create a biological tissue frostbite model and a frostbite evaluation method. By obtaining the relative blood flow change rate through laser speckle, a relationship is established between this rate and the grading of biological tissue frostbite sections. Thus, biological tissue frostbite evaluation and grading can be performed solely by obtaining the relative blood flow change rate through laser speckle.

[0044] The present invention will now be described in detail.

[0045] As attached Figure 1 As shown, this embodiment of the invention provides a device for establishing a biological tissue frostbite model and evaluating the degree of frostbite, which mainly includes a spray cooling system, a laser speckle blood flow imaging system, an infrared thermal imager temperature measurement system, a control and data acquisition system, and a sample stage.

[0046] The spray cooling system includes a refrigerant storage tank, a nitrogen pressurization tank, a solenoid valve, nozzles, and a pressure sensor.

[0047] A spray cooling system is used for frostbitten live biological tissue samples. A laser speckle blood flow imaging system is used to monitor blood flow changes at the frostbitten site; an infrared thermal imager is used to monitor temperature changes at the cooled site. A control and data acquisition system is used for the operation and data acquisition of each measuring device.

[0048] Figure 1 This is a schematic diagram of a frostbite model fabrication and frostbite severity assessment device system, illustrating the hardware components and logical relationships between them. As shown in the diagram, the entire system is laid out around a sample stage, on which biological tissue samples (such as rabbit ears) to be fabricated are fixed. Around the sample stage, there are three main functional modules: Spray cooling system: Components: The diagram clearly shows the refrigerant receiver, nitrogen pressurization tank, two solenoid valves (soleoid valve 1 and solenoid valve 2), nozzle, and two pressure sensors (pressure sensor 1 and pressure sensor 2).

[0049] Connections and Workflow: The nitrogen pressurization tank is connected to the top of the refrigerant receiver tank via a pipe and solenoid valve 2 to apply pressure to the refrigerant. The outlet of the refrigerant receiver tank is connected to a nozzle via a pipe and solenoid valve 1. The nozzle is suspended above the sample stage, directly above the frostbitten biological tissue sample. Pressure sensor 1 monitors the pressure inside the refrigerant receiver tank, and pressure sensor 2 monitors the pressure inside the nitrogen pressurization tank. The feedback signals from both sensors are connected to the control system.

[0050] The system design enables precise control of refrigerant injection. The pressurization process is controlled by solenoid valve 2, and the injection start / stop is controlled by solenoid valve 1. Two pressure sensors ensure the stability and sufficiency of the injection pressure, thereby guaranteeing the repeatability of the frostbite model.

[0051] Monitoring system: Infrared thermal imager: Its probe is aimed at the biological tissue sample on the sample stage. Its function is to monitor the temperature of the sample surface in real time and transmit the temperature data to the control system. This is a key feedback loop for achieving precise control of frostbite time.

[0052] Laser speckle blood flow imaging system: Its imaging probe is also aimed at the biological tissue sample. Its function is to monitor the blood perfusion of the frostbitten area and its surroundings in real time, generate blood flow distribution images and data, and transmit them to the control system. This is the core data source for achieving non-invasive, dynamic evaluation of the degree of frostbite.

[0053] Control and data acquisition system: Connections: The diagram clearly shows that the control system is connected to all other components—receiving signals from two pressure sensors, an infrared thermal imager, and a laser speckle blood flow imaging system, and issuing control commands to two solenoid valves. The control system is the brain of the entire device, responsible for coordinating the work of each component: controlling pressurization and injection based on pressure feedback, controlling frostbite time based on temperature feedback, and synchronously collecting and storing all monitoring data. This diagram fully reveals the hardware structure and working principle of the invention, clearly demonstrating the connections and collaboration between the components, and embodying the core design concept of combining "precise modeling" with "synchronous monitoring."

[0054] Figure 2 This intuitively demonstrates the specific implementation steps of the method of the present invention, and is a... Figure 1 A detailed breakdown of the working logic of the central control system. This can be mainly divided into the following stages: 1. Preparation and Initialization Phase: Sample fixation: Fix the frostbite sample to be prepared (such as rabbit or rat ear) onto the sample stage.

[0055] Equipment focusing: Turn on and adjust the infrared thermal imager and laser speckle blood flow imager to accurately focus on the sample surface.

[0056] System pressurization: Open solenoid valve 2 to pressurize the refrigerant receiver to the appropriate pressure via the nitrogen pressurization tank, and monitor the pressure using pressure sensors 1 and 2. Close solenoid valve 2 once the pressure reaches the target level. If pressure sensor 2 detects insufficient pressure in the nitrogen tank, it needs to be replaced.

[0057] 2. Model building phase (frostbite process): Start cooling: Open solenoid valve 1, and the pressurized refrigerant jets from the nozzle onto the sample surface to begin cooling.

[0058] Simultaneous monitoring: As the nozzle opens, the infrared thermal imager and the laser speckle blood flow imager begin to work, collecting temperature and blood flow data respectively.

[0059] Precise timing: This is one of the key innovations of this invention. The flowchart clearly indicates that the frostbite time is not calculated from the start of spraying, but rather from the point after the surface temperature of the sample to be frostbitten drops to 0°C. The system starts timing when the infrared thermal imager detects that the temperature has dropped to 0°C.

[0060] End of cooling: When the preset frostbite time is reached, the control system closes solenoid valve 1 and stops cooling.

[0061] 3. Post-monitoring and data collection phase: Short-term continuous monitoring: After cooling is stopped, the system continues to collect data synchronously and continuously for 5 minutes using both the infrared thermal imager and the laser speckle blood flow imager. This is used to observe blood flow and temperature changes during the initial rewarming phase.

[0062] Long-term intermittent monitoring: After 5 minutes, turn off the infrared thermal imager and keep only the laser speckle blood flow imager on for long-term monitoring. Data is collected every hour for 3 days. This is used to track the long-term evolution of tissue microcirculation after frostbite until the damage stabilizes.

[0063] 4. Data Analysis and Model Building Phase: Gold standard determination: Three days later, pathological analysis of frostbite sample sections is performed as the "gold standard" for determining the degree of frostbite.

[0064] Calculate the rate of change in blood flow: Using the collected data, calculate the relative rate of change in blood flow before and after frostbite.

[0065] Establishing the relationship: By setting different frostbite times and repeating all the above steps, sufficient data samples were collected. Finally, a correlation analysis was performed between the relative change rate of blood flow and the pathological gold standard to establish a quantitative relationship between the degree of frostbite and the relative change index of blood flow.

[0066] As attached Figure 2As shown, the steps of establishing a biological tissue frostbite model and evaluating the degree of frostbite are as follows: First, fix the frostbite sample to be prepared on the sample stage. The frostbite sample can be the ear or skin of a live rabbit or rat. Turn on the infrared thermal imager and the laser speckle blood flow imager, and adjust their focal lengths to accurately focus on the sample surface. Open the solenoid valve 2 in the spray cooling system to pressurize the refrigerant reservoir to a suitable pressure through the nitrogen pressurization tank to ensure sufficient pressure for stable refrigerant spraying. During the pressurization process, pressure sensors 1 and 2 monitor the pressure of the refrigerant reservoir and the nitrogen pressurization tank, respectively. After the refrigerant reservoir reaches the suitable pressure, close the solenoid valve 2. If the pressure sensor 2 detects insufficient pressure in the nitrogen pressurization tank, the nitrogen tank needs to be replaced to ensure sufficient pressurization pressure. Set the frostbite time, adjust the nozzle angle and the distance between the nozzle and the sample to be frostbitten, open the solenoid valve 1 of the refrigerant reservoir, and the pressurized refrigerant jets from the nozzle onto the surface of the sample to be frostbitten, starting the cooling process. The frostbite time is defined as the cooling duration after the surface of the sample to be frostbitten drops to 0°C. Simultaneously with the nozzle opening, the infrared thermal imager and laser speckle blood flow imager begin operation. The laser speckle blood flow imager measures changes in blood flow within the sample to be frostbitten, while the infrared thermal imager measures the surface temperature of the frostbitten sample. The frostbite time is calculated starting when the temperature drops to 0°C. Upon reaching the set frostbite time, the solenoid valve is closed for 1.5 minutes. Within this timeframe, the laser speckle blood flow imager and infrared thermal imager continuously and synchronously acquire blood flow data and the surface temperature of the frostbitten sample. After 5 minutes, the infrared thermal imager is turned off, and only the laser speckle blood flow imager acquires blood flow data from the frostbitten surface. Data is collected every 1 hour, and collection ceases after 3 days. The degree of frostbite is determined based on the frostbite severity evaluation criteria and the preparation of frostbite sample sections, serving as the gold standard for frostbite severity. The relative change rate of blood flow before and after frostbite is also calculated using the following formula: BFI before BFI is used to measure the blood flow velocity of frostbitten samples before cooling. after The blood flow velocity of the sample was measured 3 days after frostbite. The above steps were repeated with different frostbite times. Sufficient data were collected to establish a relationship between the degree of frostbite and the relative change index of blood flow, thus enabling the evaluation of the degree of frostbite in biological tissues solely by monitoring the relative change rate of blood flow using a laser speckle blood flow imager.

[0067] Spray cooling combined with infrared thermal imaging allows for precise control of frostbite time. Laser speckle blood flow imaging enables non-invasive, large-area, real-time monitoring of blood flow changes in frostbitten tissue. A formula relating the degree of frostbite to the relative rate of change in blood flow in biological tissues can be established, allowing for non-invasive evaluation of the degree of frostbite simply by measuring the relative rate of change in blood flow.

[0068] This invention can be widely used for assessing the condition of frostbite. Frostbite is damage to the skin and underlying tissues caused by exposure to extremely cold environments. Frostbite typically occurs on exposed areas such as fingers, toes, ears, nose, and face. Its primary cause is the freezing of local tissues due to cold temperatures, which in turn affects blood circulation and cell health. Cold sprays are commonly used in dermatological treatments, such as cryotherapy for warts and skin growths. Improper operation, such as prolonged spraying time or too close distance, can lead to localized frostbite. Cooling sprays are often used in sports for the cold compress treatment of acute injuries, but prolonged spraying time or too close distance can also cause frostbite. In some industrial operations, the use of cooling sprays or liquid gases may accidentally come into contact with the skin, resulting in cold spray frostbite. Human tissue frostbite requires timely treatment according to its severity; therefore, the assessment of the severity of frostbite is crucial.

[0069] There are a large number of frostbite patients, but there is still a lack of rapid and effective methods for assessing the severity of frostbite. The patented technology of this invention can be used to assess the severity of frostbite in frostbite patients, which is conducive to the accurate diagnosis and treatment of frostbite sites and has great economic benefits.

[0070] Based on the patented technology of this invention, frostbite severity detection equipment can be developed, improving the accuracy and convenience of frostbite severity assessment, which is conducive to obtaining more accurate treatment parameters and improving treatment effects.

[0071] Figure 3 This is a typical visualization of temperature and blood flow distribution, showcasing the data visualization effect of this invention and reflecting the spatial distribution characteristics of temperature and blood perfusion within a specific biological tissue region. Temperature information is correlated with the degree of frostbite and can be used to characterize the damage state of the frostbitten area, while blood flow information reflects the blood perfusion status of the local tissue. Different colors in the figure represent different temperature or blood perfusion levels, typically presented in pseudo-color. For example, dark or cool colors (such as blue) usually indicate areas with lower temperatures or weaker blood perfusion, while light or warm colors (such as red and yellow) indicate areas with higher temperatures or stronger blood perfusion. This figure allows for a direct observation of the temperature and blood flow distribution characteristics of the frostbitten area. For instance, the central injury area may exhibit significant low temperatures and reduced blood perfusion, while the surrounding areas may show a gradual recovery in temperature or compensatory increase in blood flow. This visualization effectively reflects the spatial distribution characteristics of the frostbitten area and provides a foundation for subsequent data analysis. Researchers can select regions of interest (ROIs) in images for quantitative analysis, such as calculating the average temperature and average blood perfusion level of frostbitten areas, or comparing differences between different locations. Combined with... Figure 4The variation curves shown in this spatial distribution map can also be used to analyze the dynamic changes in temperature and blood perfusion in the same area before and after frostbite. This invention demonstrates that the proposed imaging and analysis method can effectively and intuitively present the spatial distribution information of tissue temperature and blood perfusion, providing basic image data for frostbite severity assessment and quantitative analysis.

[0072] Figure 4 This is a graph showing the change in blood flow velocity over time, illustrating the results of quantitative analysis of monitoring data using this invention. The curve clearly demonstrates the dynamic evolution of tissue blood flow velocity from before frostbite, during frostbite, to a period of time after frostbite.

[0073] Baseline period: The initial part of the curve is relatively stable, representing the normal blood flow velocity before frostbite (BFI ~before~).

[0074] Rapid descent phase: After the initiation of spray cooling, as tissue temperature decreases, blood flow velocity drops sharply until it approaches zero. This reflects the vasoconstriction and blood flow stagnation caused by hypothermia.

[0075] Plateau phase: During the course of frostbite, blood flow velocity remains at an extremely low level.

[0076] Recovery period: After cooling is stopped, the curve changes. For mild frostbite, blood flow may recover rapidly after rewarming, or even reactive hyperemia may occur (the curve may exceed the baseline); for severe frostbite, blood flow may not recover, and the curve remains low. The curve shown in the figure is slightly below the baseline after recovery, which may represent a certain degree of irreversible damage.

[0077] The basis of quantitative analysis: This curve is the foundation for calculating the "relative rate of change of blood flow" (rBFI). The BFI before (before cooling) and BFI after (a specific time point after frostbite) required in the formula can be directly read from the curve.

[0078] Evidence of dynamic monitoring: The curve itself proves that this application can achieve long-term, dynamic tracking of blood flow changes in the same area, which is something that traditional pathological sectioning methods cannot do.

[0079] Correlation with frostbite severity: Different shapes of the curve (such as the speed of recovery and the level of recovery) themselves contain information about the severity of frostbite. By comparing this with... Figure 2 By associating the pathology gold standard with the relevant data, a quantitative evaluation model can be established.

[0080] Figure 4 Quantifying the physiological changes (blood flow) after frostbite into a dynamic curve provides the most direct data support for establishing a quantitative relationship between "blood flow and frostbite severity".

[0081] Figure 5 This is a three-dimensional dynamic curve of blood flow changes under different spray durations, used to illustrate the response characteristics of tissue blood perfusion over time during cold spray stimulation. The horizontal axis represents time t (ms), the vertical axis represents the blood flow index BFI (au), and the lateral axis represents the spray duration (ms). Curves of different colors and at different heights correspond to the blood flow changes under different spray durations.

[0082] As can be visually observed from the figures, blood flow signals in each group exhibited varying degrees of fluctuation after the spraying began. When the spray duration was short, the amplitude of blood flow changes was relatively small; as the spray duration increased, both the amplitude and duration of blood flow changes gradually increased, reflecting the more significant impact of stronger cold stimulation on local microcirculation. Some curves showed a certain degree of blood flow recovery in the later stages or after the spraying, which may be related to the regulation or recovery process of local blood flow.

[0083] By comparing blood flow change curves under different spray durations, the relationship between cold stimulation intensity and dynamic blood flow response can be analyzed, thus providing a basis for assessing the severity and evolution of frostbite. Figure 3 The spatial distribution results of temperature and blood flow shown in this invention enable visualization and quantitative analysis of microcirculation changes during tissue frostbite from both spatial and temporal dimensions.

[0084] This invention aims to solve the technical problem that existing technologies for assessing the severity of frostbite rely on invasive, offline pathological analysis, which cannot achieve real-time, non-invasive, and quantitative dynamic monitoring. This invention also provides a method for assessing the severity of frostbite in biological tissues, comprising: Temperature data of the biological tissue sample surface monitored by a first monitoring device is acquired. Based on the temperature data, a cooling system is controlled to execute a preset cooling strategy on the biological tissue sample. During and after the execution of the cooling strategy, the temperature data and blood flow data of the biological tissue sample monitored by a second monitoring device are simultaneously acquired and stored. Based on the acquired blood flow data, evaluation parameters characterizing the degree of frostbite of the biological tissue sample are calculated.

[0085] This invention provides a method for evaluating the severity of frostbite in biological tissues, aiming to address the technical problem that existing technologies rely on invasive, offline pathological analysis for frostbite severity evaluation, failing to achieve real-time, non-invasive, and quantitative dynamic monitoring. This method simultaneously collects temperature and blood perfusion data of biological tissue samples during and after controlled cold stimulation, and calculates quantitative evaluation parameters based on the blood flow data. This enables dynamic and objective assessment of the development and recovery process of frostbite, providing a powerful tool for research on frostbite mechanisms and evaluation of treatment effects. This method can be applied to biomedical research fields such as in vivo animal experimental models and isolated tissue studies.

[0086] This invention provides a method for evaluating the degree of frostbite in biological tissues, comprising steps S1, S2, S3, and S4. Step S1 involves acquiring temperature data of the surface of a biological tissue sample monitored by a first monitoring device. Step S2 involves controlling a cooling system to execute a preset cooling strategy on the biological tissue sample based on the temperature data. Step S3 involves simultaneously acquiring and storing the temperature data and blood flow data of the biological tissue sample monitored by a second monitoring device during and after the execution of the cooling strategy. Step S4 involves calculating evaluation parameters characterizing the degree of frostbite in the biological tissue sample based on the acquired blood flow data. This method achieves closed-loop precise control of the cooling process using temperature data as feedback, ensuring the repeatability of the frostbite model. Simultaneously, by introducing non-invasive blood flow monitoring technology, the evaluation focus shifts from tissue morphology (pathology) to functional state (blood perfusion), thereby achieving real-time, dynamic, and quantitative assessment of the same injury site.

[0087] In this embodiment, step S1 can be specifically executed as follows: A first monitoring device (e.g., an infrared thermal imager) performs non-contact temperature measurement on the biological tissue sample mounted on the sample stage to obtain a real-time temperature distribution map and average temperature data of a specific region (region of interest, ROI). The first monitoring device transmits the acquired temperature data stream to a data processing unit (e.g., a computer) via a data interface (e.g., USB, GigE Vision, etc.). The data processing unit reads and parses the temperature data stream by calling the corresponding driver or API interface, stores the temperature information in memory, and can use it for real-time display and analysis. This step provides the data foundation for subsequent precise temperature-based control.

[0088] In this embodiment, step S2 can be specifically executed as step S21. Step S21 is used to achieve precise control of the frostbite duration. When executing step S21, it includes sub-steps S211, S212, and S213. Sub-step S211 is to identify the moment when the surface temperature of the biological tissue sample drops to a preset phase transition point based on the temperature data. Specifically, the data processing unit receives and analyzes the temperature data from the first monitoring device in real time. By comparing the current temperature value with the preset phase transition point (e.g., 0°C), when the temperature data of several consecutive frames (e.g., 5 frames) are all equal to or lower than the phase transition point, the moment is determined to be the phase transition point moment t0. Sub-step S212 is to start timing from the moment. That is, a timer is started in the processor, and the timing start point is set to t0. Sub-step S213 is to determine the timing when the timer reaches the preset cooling duration t. holdWhen the cooling system stops cooling the biological tissue sample, the system can be controlled to cease cooling. This can be achieved by sending a stop command to the cooling system's control unit (e.g., a switching output module controlling a solenoid valve), for example, by closing the solenoid valve controlling refrigerant injection. This control logic ensures that the degree of frostbite is primarily determined by the "time the tissue is frozen," effectively eliminating the influence of individual differences in cooling rate on model consistency. As a preferred embodiment, the preset phase transition point can be set to 0°C, since the freezing point of water (0°C) is a typical physical threshold for tissue to undergo a freezing phase transition.

[0089] Step S2 may also optionally include monitoring and controlling the operating status of the cooling system. Step S22 is used to implement this function. When step S22 is executed, it includes sub-steps S221 and S222. Sub-step S221 is to acquire pressure data characterizing the operating status of the cooling system. Specifically, pressure signals are acquired in real time by pressure sensors installed on the refrigerant reservoir and / or pressurization unit, and transmitted to the data processing unit via an analog-to-digital converter (ADC) or a digital interface. Sub-step S222 is to control the operating status of the cooling system based on the pressure data. This sub-step may further include two response modes. The first response mode: responding to data P characterizing the pressure of the refrigerant reservoir. tank Below the first preset pressure threshold P th1 The pressurization unit pressurizes the refrigerant reservoir of the cooling system. This can be achieved by opening a solenoid valve controlling the pressurization gas path or by starting a miniature air pump to maintain a stable injection pressure. The second response method responds to data P characterizing the pressure of the pressurization unit. source Below the second preset pressure threshold P th2 The system outputs prompts. For example, a text or sound alarm such as "Insufficient air pressure, please replace" pops up on the user interface, prompting the operator to intervene. The introduction of step S22 significantly improves the automation level and reliability of the entire cooling process, ensuring the consistency of experimental conditions. Steps S21 and S22 can be executed in parallel, together forming a complete cooling control strategy.

[0090] In this embodiment, step S3 can be specifically executed as step S31. When step S31 is executed, it includes sub-steps S311 and S312. Sub-step S311 involves controlling the first monitoring device and the second monitoring device to continuously and synchronously acquire data during a first preset time period T1 after the cooling system stops cooling. During this period, the data processing unit simultaneously records temperature data and blood flow data at a high sampling rate (e.g., 10 Hz), and uses a system clock or hardware trigger signal to ensure that the timestamps of the two types of data are accurately aligned, so as to facilitate subsequent analysis of rapid physiological changes in the early stage of rewarming. Sub-step S312 involves controlling the second monitoring device to intermittently acquire data according to a preset sampling interval Δt after the first preset time period T1 ends, continuing for a second preset time period T2. In a specific implementation, T1 can be 5 minutes, T2 can be 3 days, and Δt can be 1 hour. During the execution of sub-step S312, the data acquisition of the first monitoring device can be stopped to save resources. The phased and strategy-based data acquisition scheme in step S31 takes into account both the short-term, high-frequency needs of capturing rapidly changing processes and the efficiency of tracking long-term evolution processes, and constructs a complete dataset for the analysis of the entire frostbite process.

[0091] In this embodiment, step S4 can be specifically executed as step S41. Step S41 is used to calculate the quantified frostbite evaluation parameters. When executing step S41, it specifically involves calculating the relative rate of change of blood flow in the biological tissue sample based on the first blood flow data collected before the cooling operation begins and the second blood flow data collected at a preset time point after the cooling operation ends. The data processing module extracts the blood flow value at a stable moment before the start of cooling (e.g., the average value of 10 seconds before cooling) from the stored time-series blood flow data as the BFI. before The blood flow value at a preset time point after the cooling period (e.g., the 3rd day after the cooling period) is extracted as the BFI. after Then, calculations were performed according to the recorded formula:

[0092] in, The relative rate of change of blood flow. This is the first blood flow data. This is the second blood flow data. The processor performs this mathematical operation to obtain a quantitative index characterizing the tissue's ability to recover blood flow. A negative rBFI value, and the larger the absolute value, the more severe the microcirculatory disturbance caused by frostbite. This method transforms the evaluation criteria from subjective morphological observation to objective numerical values, achieving quantitative grading.

[0093] It also includes: obtaining the gold standard for the degree of frostbite obtained by pathological analysis of the biological tissue samples; Establish the correlation between the evaluation parameters and the gold standard for the degree of frostbite.

[0094] The simultaneous acquisition and storage of temperature data and blood flow data of the biological tissue sample monitored by the second monitoring device during and after the execution of the cooling strategy specifically includes: During a first preset time period after the cooling system stops cooling, the first monitoring device and the second monitoring device are controlled to continuously and synchronously collect data. After the first preset time period ends, the second monitoring device is controlled to perform intermittent data collection according to the preset sampling interval for a second preset time period.

[0095] Specifically, after the first preset time period ends, the data acquisition of the first monitoring device is stopped.

[0096] The controlled cooling system implements a preset cooling strategy for the biological tissue sample, and further includes: Acquire pressure data to characterize the operating state of the cooling system; The operating status of the cooling system is controlled based on the pressure data.

[0097] The control of the operating state of the cooling system based on the pressure data specifically includes: In response to the pressure data being lower than a first preset pressure threshold, the pressurization unit is controlled to pressurize the refrigerant storage tank of the cooling system; in response to the data representing the pressure of the pressurization unit being lower than a second preset pressure threshold, a prompt message is output.

[0098] The first monitoring device is an infrared thermal imager, and the second monitoring device is a laser speckle blood flow imaging system.

[0099] In this embodiment, the method may further include step S5. Step S5 is used to establish a bridge between non-invasive evaluation parameters and invasive gold standards, thereby verifying and enhancing the scientific validity and practicality of the method. Step S5 specifically includes obtaining the gold standard for frostbite severity obtained from pathological analysis of the biological tissue samples; and establishing the correlation between the evaluation parameters (such as rBFI) and the gold standard for frostbite severity. In specific implementation, multiple biological tissue samples that have undergone different preset cooling strategies (such as different cooling durations) can have their rBFI values ​​obtained by performing steps S1 to S4 respectively, and then the corresponding samples can be processed into pathological sections. Pathologists can then classify the frostbite grades (such as grade I, grade II, and grade III) based on criteria such as cell necrosis and inflammatory infiltration. Finally, statistical analysis methods (such as linear regression, logistic regression, ROC curve analysis, etc.) are used to analyze the correlation between rBFI values ​​and pathological grades to establish corresponding relationships or judgment thresholds. For example, an empirical threshold of "rBFI < -70% corresponds to grade III frostbite" can be derived. Step S5 enables the subsequent non-invasive measurement of rBFI to infer the degree of frostbite, which is in good agreement with the pathological gold standard, greatly improving the evaluation efficiency.

[0100] In practice, the first monitoring device is an infrared thermal imager, and the second monitoring device is a laser speckle blood flow imaging system. The infrared thermal imager measures temperature non-contactly by detecting infrared radiation from the surface of biological tissue. The laser speckle blood flow imaging system calculates the blood flow index (BFI), which characterizes blood flow velocity or perfusion volume, by emitting a laser beam onto the tissue surface and analyzing the spatiotemporal dynamic changes of the speckle pattern formed by its reflection. Both technologies are non-contact and non-invasive monitoring methods, making them highly suitable for long-term, dynamic observation of the same living sample.

[0101] This application also provides a device for evaluating the degree of frostbite in biological tissues, used to perform the above-described method. The device includes a first monitoring module, a control module, a data acquisition module, and a data processing module.

[0102] The first monitoring module is used to acquire temperature data of the surface of biological tissue samples monitored by the first monitoring device. This module can achieve data acquisition by calling the SDK or driver of the infrared thermal imager.

[0103] The control module is used to control the cooling system to execute a preset cooling strategy on the biological tissue sample based on the temperature data. Specifically, this module can be used to execute sub-steps S211 to S213, as well as sub-steps S221 and S222.

[0104] The data acquisition module is used to synchronously acquire and store the temperature data and the blood flow data of the biological tissue sample monitored by the second monitoring device during and after the execution of the cooling strategy. Specifically, this module can be used to execute sub-steps S311 and S312 to realize the synchronous triggering, reception and storage of data.

[0105] The data processing module is used to calculate evaluation parameters characterizing the degree of frostbite in the biological tissue sample based on the collected blood flow data. Specifically, this module can be used to execute step S41, calculating the relative rate of change of blood flow.

[0106] Each module can be integrated into the same data processing device (such as an industrial computer or a computer) and its functions can be implemented through software programming; alternatively, some functions can be implemented by independent hardware modules (such as data acquisition cards or PLC controllers).

[0107] This invention achieves the following beneficial effects by simultaneously acquiring and processing blood flow data from biological tissue samples during controlled cooling. The invention directly acquires blood flow data from biological tissue samples monitored by a second monitoring device and calculates evaluation parameters based on this data. Blood flow is a core physiological indicator reflecting the state of tissue microcirculation and cell activity, and is directly related to the degree of frostbite. By acquiring and processing this blood flow data, a non-invasive, in-situ evaluation of the degree of frostbite is achieved, avoiding the invasive sampling operations required for traditional pathological analysis. Because blood flow data can be continuously or intermittently acquired synchronously during the cooling process and subsequent recovery, dynamic, real-time monitoring of the entire evolution of frostbite at the same injury site can be achieved. This overcomes the limitations of traditional methods, which can only provide single-point-of-time, offline analysis results. Evaluation parameters calculated based on blood flow data, such as the relative rate of change of blood flow, are objective quantitative indicators. This indicator eliminates subjective human factors in the evaluation process and achieves quantitative grading of the severity of frostbite. Furthermore, by establishing a correlation between this evaluation parameter and the gold standard for frostbite severity, the quantitative indicators obtained from non-invasive, real-time monitoring can be correlated with clinically recognized pathological conclusions. This significantly improves evaluation efficiency and expands its application scenarios while ensuring the scientific rigor and accuracy of the evaluation.

[0108] This application also provides an electronic device. Such an electronic device includes a processor and a memory.

[0109] Memory is used to store computer programs. Memory can be random access memory (RAM), read-only memory (ROM), or non-volatile memory such as flash memory.

[0110] The processor executes the computer program stored in the memory to implement the steps in the aforementioned method for evaluating the degree of frostbite in biological tissues. The processor can be an integrated circuit chip with signal processing capabilities, such as a central processing unit (CPU), digital signal processor (DSP), graphics processing unit (GPU), or microcontroller unit (MCU). The processor and memory can be connected via a bus, such as a PCI bus or EISA bus. The electronic device may also include a communication interface for communicating with other devices, such as a first monitoring device, a second monitoring device, or the actuator of the cooling system. It may also include input / output interfaces for connecting peripherals such as a monitor, keyboard, and mouse.

[0111] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the biological tissue frostbite assessment method described above.

[0112] The computer-readable storage medium can be any medium capable of storing program code, such as cloud storage, USB flash drive, portable hard drive, read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0113] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0114] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A device for establishing a biological tissue frostbite model and evaluating the degree of frostbite, characterized in that, include: Sample stage, used to hold biological tissue samples; A spray cooling system, with its nozzles facing the sample stage, is used to spray and cool the biological tissue sample to establish a frostbite model; An infrared thermal imager, whose field of view covers the biological tissue sample, is used to monitor the surface temperature of the biological tissue sample in real time. A laser speckle blood flow imaging system, with an imaging field covering the biological tissue sample, is used for non-invasive, real-time monitoring of blood flow changes in the frostbitten area of ​​the biological tissue sample; and The control system is connected to the spray cooling system, the infrared thermal imager, and the laser speckle blood flow imaging system, respectively, and the control system is configured as follows: Based on the temperature monitored by the infrared thermal imager, the spray cooling system is controlled to execute a preset cooling strategy to create a biological tissue frostbite model with a predetermined degree of frostbite. The temperature data monitored by the infrared thermal imager and the blood flow data monitored by the laser speckle blood flow imaging system are collected and stored simultaneously for subsequent frostbite severity analysis.

2. The apparatus according to claim 1, characterized in that, The spray cooling system includes: Refrigerant receiver tank, used to store refrigerant; A pressurization unit, connected to the refrigerant storage tank, is used to pressurize the refrigerant in the refrigerant storage tank; A nozzle, connected to the outlet of the refrigerant reservoir via a pipe, is used to spray pressurized refrigerant onto the surface of the biological tissue sample; At least one solenoid valve is disposed on the pipeline between the refrigerant receiver and the nozzle, and connected to the control system, for controlling the on / off state of refrigerant injection; and At least one pressure sensor is disposed in the refrigerant reservoir and / or the pressurization unit and connected to the control system for monitoring pressure.

3. The apparatus according to claim 2, characterized in that, The control system is also configured to: based on the pressure monitored by the pressure sensor, when the pressure of the refrigerant storage tank is lower than a first preset threshold, control the pressurization unit to pressurize the refrigerant storage tank; When the pressure of the pressurizing unit is lower than the second preset threshold, a prompt signal is output to replace or replenish the pressurizing medium.

4. The apparatus according to claim 1, characterized in that, The control system is configured to execute the preset cooling strategy, including: Based on the temperature data monitored by the infrared thermal imager, identify the moment when the surface temperature of the biological tissue sample drops to 0°C; The timer starts from that moment and continues until the preset frostbite duration is reached; When the preset frostbite duration is reached, the spray cooling system is controlled to stop cooling.

5. The apparatus according to claim 1, characterized in that, The control system is also configured to: Within a first preset time after the spray cooling system stops cooling, the infrared thermal imager and the laser speckle blood flow imaging system are controlled to continue to synchronously acquire data; After the first preset time, the infrared thermal imager is controlled to stop acquiring data, and the laser speckle blood flow imaging system is controlled to intermittently acquire data at preset time intervals for a second preset time.

6. The apparatus according to claim 1, characterized in that, The control system is also configured to: Based on the collected blood flow data, the relative rate of change in blood flow before and after frostbite was calculated; the formula for the relative rate of change in blood flow is: In the formula, BFI before BFI is used to measure the blood flow velocity of frostbitten samples before cooling. after The blood flow velocity of the sample 3 days after frostbite.

7. The apparatus according to claim 1, characterized in that, The control system is further configured to: generate a temperature change curve of the surface of the biological tissue sample based on the temperature data monitored by the infrared thermal imager; and generate a blood flow distribution map and / or blood flow change curve of the frostbite area based on the blood flow data monitored by the laser speckle blood flow imaging system.

8. A system for establishing a biological tissue frostbite model and evaluating the severity of frostbite, characterized in that, include: The apparatus as described in any one of claims 1 to 7; as well as A pathological analysis device is used to perform pathological analysis on biological tissue samples processed by the device to determine the degree of frostbite as the gold standard.

9. A method for establishing a biological tissue frostbite model and evaluating the degree of frostbite using the apparatus described in any one of claims 1 to 7, characterized in that, Includes the following steps: S1: Sample fixation, fixing the biological tissue sample onto the sample stage; S2: The system focuses, and the infrared thermal imager and laser speckle blood flow imaging system are started and adjusted to focus on the surface of the biological tissue sample; S3: Model establishment: The spray cooling system is activated through the control system to spray and cool the biological tissue sample according to the preset cooling strategy in order to establish a frostbite model. S4: Data acquisition. During and after the model establishment process, the control system synchronously acquires and stores the temperature data monitored by the infrared thermal imager and the blood flow data monitored by the laser speckle blood flow imaging system. S5: Data analysis, based on the collected blood flow data, calculate physiological parameters used to characterize the degree of frostbite.

10. The method according to claim 9, characterized in that, It also includes step S6: establishing evaluation criteria, performing pathological analysis on biological tissue samples that have undergone different preset cooling strategies to obtain the gold standard for their frostbite degree; and performing correlation analysis between the relative change rate of blood flow and the gold standard for frostbite degree to establish a relationship or threshold for evaluating the degree of frostbite.

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