A liquid nitrogen freezing device

Abstract

The present invention discloses a liquid nitrogen freezing device, which relates to medical equipment. The device comprises: a camera with a pan / tilt head, for acquiring a first skin lesion image and a second skin lesion image before and after treatment; a control module, for determining the skin lesion area of the skin lesion region based on the first skin lesion image, so as to determine a default treatment distance and a default treatment time; a timer, for timing the treatment time of liquid nitrogen cryotherapy; and a non-contact thermometer, for measuring the temperature of the skin lesion region being treated. The control module activates a spraying function after a treatment nozzle is aligned with the skin lesion region and reaches the default treatment distance from the skin lesion region, so as to cause the treatment nozzle to spray liquid nitrogen toward the skin lesion region. During the liquid nitrogen cryotherapy of the skin lesion region, the control module acquires the treatment time, temperature, and the second skin lesion image, so as to stop the spraying function when at least one of the treatment time, temperature, and the treated skin lesion region in the second skin lesion image satisfies a spraying stop condition.

Description

Technical Field

[0001] The present invention relates to medical equipment, in particular to liquid nitrogen freezing equipment. Background Art

[0002] Liquid nitrogen cryotherapy is a commonly used physical therapy in hospitals. Liquid nitrogen vaporization absorbs heat, creating a low temperature that affects diseased tissue, causing it to necrotize and slough off. Liquid nitrogen cryotherapy is a combination of cryobiology. When frozen, normal cells undergo irreversible damage, rapidly killing cells in the affected area. After freezing, the affected lesions gradually slough off, allowing them to gradually recover.

[0003] At present, liquid nitrogen cryotherapy usually adopts two methods. The first is to roll cotton wool on the tip of a cotton swab so that the size of the cotton swab head is substantially the same as the size of the skin lesion (i.e., the skin diseased part), and then dip it in liquid nitrogen and apply it to the skin lesion for freezing to kill the affected area cells. The treatment operation of this method determines the treatment time entirely according to the clinical experience of clinical nurses. If the time is too long, the skin lesion is prone to blistering and easily damages the surrounding normal skin. If the time is too short, the skin lesion is not completely frozen and easily relapses. The second is to adopt a liquid nitrogen cryotherapy device with a treatment nozzle and a wrench, and the treatment nozzle is controlled by the wrench to spray liquid nitrogen to the skin lesion area. The treatment operation of this method requires a clinical nurse to adjust the treatment distance and decide the treatment time according to clinical experience. If the distance is too close, the time is too long, the skin lesion is prone to blistering and easily damages the surrounding normal skin. On the contrary, if the distance is too far, the time is too short, and the skin lesion is not completely frozen and easily relapses. Summary of the Invention

[0004] The present invention provides a liquid nitrogen freezing device, which aims to reduce damage to the patient's normal skin, increase the cure rate of the patient's skin lesions, and improve the patient's satisfaction.

[0005] The present invention provides a liquid nitrogen freezing device, comprising: a treatment nozzle, a liquid nitrogen supply pipeline, a liquid nitrogen valve connected to the liquid nitrogen supply pipeline, and a liquid nitrogen container connected to the treatment nozzle through the liquid nitrogen supply pipeline; the device further comprising: a camera with a pan / tilt head, configured to capture a first skin lesion image before liquid nitrogen cryotherapy is performed on the skin lesion area, and to capture a second skin lesion image during liquid nitrogen cryotherapy of the skin lesion area; a control module, configured to determine the skin lesion area of the skin lesion area based on the first skin lesion image, and to determine a default treatment distance between the treatment nozzle and the skin lesion area and a default treatment time of liquid nitrogen cryotherapy according to the skin lesion area; a timer, configured to start timing when a spraying function is activated and stop timing when the spraying function is stopped, so as to obtain the treatment time of liquid nitrogen cryotherapy; and a non-contact thermometer, configured to start temperature measurement when the spraying function is activated, so as to monitor the skin lesion area receiving liquid nitrogen cryotherapy. The control module measures the temperature of the lesion area and stops the temperature measurement at the same time as the spraying function is stopped; wherein, after the treatment nozzle is aimed at the lesion area and the distance from the lesion area reaches the default treatment distance, the control module starts the spraying function, connects the liquid nitrogen container and the treatment nozzle by opening the liquid nitrogen valve on the liquid nitrogen supply pipeline, and causes the treatment nozzle to spray liquid nitrogen toward the lesion area; wherein, during the liquid nitrogen cryotherapy of the lesion area, the control module obtains the treatment time of the liquid nitrogen cryotherapy from the timer, obtains the temperature of the lesion area receiving the liquid nitrogen cryotherapy from the non-contact thermometer, and obtains a second skin lesion image from the camera; when at least one of the treatment time, the temperature, and the treated skin lesion area in the second skin lesion image meets the spraying stop condition, the spraying function is stopped, and the liquid nitrogen valve on the liquid nitrogen supply pipeline is closed to cut off the passage for the liquid nitrogen container to transport liquid nitrogen to the treatment nozzle.

[0006] Preferably, the first skin lesion image includes the skin lesion area and a reference object set near the skin lesion area; the control module determines the skin lesion area of the skin lesion area based on the first skin lesion image, including: identifying the skin lesion area and the reference object from the first skin lesion image; counting the number of pixels of the skin lesion area and the number of pixels of the reference object in the first skin lesion image; and determining the skin lesion area of the skin lesion area according to the number of pixels of the skin lesion area and the number of pixels of the reference object in the first skin lesion image and the known actual area of the reference object.

[0007] Preferably, the control module determines the correspondence between the number of pixels and the actual area based on the number of pixels of the reference object in the first skin lesion image and the known actual area of the reference object, and determines the lesion area of the lesion area based on the number of pixels of the lesion area in the first skin lesion image and the correspondence between the number of pixels and the actual area.

[0008] Preferably, the device further comprises: a first storage unit for storing a first correspondence table between skin lesion area and treatment distance and a second correspondence table between skin lesion area and treatment time when using treatment nozzles of different specifications.

[0009] Preferably, the control module determines the default treatment distance between the treatment nozzle and the lesion area and the default treatment time of liquid nitrogen cryotherapy based on the lesion area of the lesion area, including: searching the first correspondence table stored in the first storage unit to find the treatment distance corresponding to the lesion area of the lesion area as the default treatment distance; searching the second correspondence table stored in the first storage unit to find the treatment time required for using the treatment nozzle when performing liquid nitrogen cryotherapy on the lesion area as the default treatment time.

[0010] Preferably, the spray stop conditions include: the treatment time reaches or exceeds the default treatment time; the temperature reaches a preset target temperature; the edge of the treated skin lesion area in the second skin lesion image coincides with the edge of the skin lesion area.

[0011] Preferably, the camera is further used to capture a third skin lesion image after liquid nitrogen cryotherapy is performed on the skin lesion area.

[0012] Preferably, the control module is further used to determine the amount of liquid used in this treatment based on the specifications of the treatment nozzle and the treatment time; and / or, before performing liquid nitrogen cryotherapy on the lesion area, determine a first distance between the camera lens and the center of the lesion area, and after performing liquid nitrogen cryotherapy on the lesion area, determine a second distance between the camera lens and the center of the lesion area, and determine the lesion depth based on the first distance and the second distance.

[0013] Preferably, the device also includes: a second storage unit for storing treatment information of each patient including lesion area, lesion depth, default treatment distance, default treatment time, actual treatment time, liquid volume, and a third lesion image, so as to determine the treatment depth, treatment distance, treatment time, and liquid volume suitable for different lesion areas by analyzing the treatment information of multiple patients.

[0014] Preferably, the touch screen is used to display the skin lesion area, skin lesion depth, default treatment distance, default treatment time, actual treatment time, liquid volume, first skin lesion image, second skin lesion image and third skin lesion image.

[0015] An embodiment of the present invention provides a liquid nitrogen freezing device that can provide a treatment distance suitable for the skin lesion area before treatment. During treatment, the device stops treatment at an appropriate time based on the treatment time, the temperature of the skin lesion area, and at least one of the treated skin lesion areas, thereby reducing damage to the patient's normal skin, improving the cure rate of the patient's skin lesions, and enhancing patient satisfaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the structure of a liquid nitrogen freezing device provided by an embodiment of the present invention;

[0017] Figure 2 This is a circuit control schematic diagram of a liquid nitrogen freezing device provided by an embodiment of the present invention;

[0018] Figure 3 This is a schematic diagram of the pan / tilt control principle provided by an embodiment of the present invention;

[0019] Figure 4 This is a schematic diagram of the telescopic rod control principle provided by an embodiment of the present invention;

[0020] Figure 5 This is a workflow diagram of the liquid nitrogen freezing equipment provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0021] It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. In the subsequent description, suffixes such as "module," "component," or "unit" used to denote components are used solely to facilitate the description of the present invention and have no inherent meaning. Therefore, "module," "component," or "unit" may be used interchangeably.

[0022] See also Figure 1 An embodiment of the present invention provides a liquid nitrogen freezing device, comprising: a base 1, a housing 2 mounted on the base 1, a liquid nitrogen container 3 mounted within the housing 2, a liquid nitrogen supply pipe 4 connected to the liquid nitrogen container 3, a liquid nitrogen supply valve (or liquid nitrogen valve) 5 connected to the liquid nitrogen supply pipe 4, and a treatment nozzle 6 connected to the liquid nitrogen supply pipe 4. Liquid nitrogen valve 5 on the liquid nitrogen supply pipe 4 is controlled to open or close the passage from the liquid nitrogen container 3 to the treatment nozzle 6.

[0023] The device may further include: a connecting mechanism 8 fixed to the side of the shell 2 and a camera 7 with a pan-tilt head mounted on the connecting mechanism 8, wherein the camera 7 is used to capture a first skin lesion image before liquid nitrogen cryotherapy is performed on the skin lesion area, capture a second skin lesion image during liquid nitrogen cryotherapy of the skin lesion area, and capture a third skin lesion image after liquid nitrogen cryotherapy of the skin lesion area.

[0024] In particular, the camera 7 is controlled by the PTZ to rotate in the horizontal direction and / or vertical direction, so that the camera 7 faces the skin lesion area and captures the first, second and third skin lesion images. Figure 3 The pan / tilt system may include a pan / tilt processing module, horizontal and vertical drive circuits, and horizontal and vertical actuators. When the pan / tilt processing module receives a pan / tilt control signal, it sends horizontal and vertical drive signals to the horizontal and vertical drive circuits, respectively, based on pan / tilt control parameters carried in the pan / tilt control signal. This causes the horizontal and vertical actuators to move in response to the horizontal and vertical drive signals, respectively, thereby enabling the lens of camera 7 to face the lesion area.

[0025] In this embodiment, the treatment nozzle 6 can be fixedly mounted on the side of the housing of the camera 7 so as to move along with the movement of the camera.

[0026] In this embodiment, the connecting mechanism 8 may have a telescopic function in the horizontal direction and / or the vertical direction. For example, the connecting mechanism adopts an electric telescopic rod, and the telescopic function of the electric telescopic rod enables the camera 7 with the pan / tilt head to produce a horizontal and / or vertical displacement relative to the housing 2. In one embodiment, see Figure 1The connecting rod 8 can be an electric telescopic rod for extending and retracting the camera 7 with a pan-tilt head in the horizontal direction. For ease of explanation, it is hereinafter referred to as the horizontal telescopic rod. Obviously, the horizontal telescopic rod 8 connects the housing 2 and the camera 7 with a pan-tilt head. By extending or retracting the horizontal telescopic rod, the camera 7 with a pan-tilt head is driven away from or closer to the housing 2, thereby adjusting the distance between the camera 7 with a pan-tilt head and the lesion area (e.g., the center of the lesion area), i.e., the treatment distance. In another embodiment, the connecting mechanism 8 can include an electric telescopic rod that extends and retracts in the horizontal direction (hereinafter referred to as the horizontal telescopic rod) and an electric telescopic rod that extends and retracts in the vertical direction (hereinafter referred to as the vertical telescopic rod). The horizontal telescopic rod is fixedly mounted with the camera 7 with a pan-tilt head. By extending or retracting the horizontal telescopic rod, the camera 7 with a pan-tilt head is driven away from or closer to the housing 2, thereby adjusting the distance between the camera 7 with a pan-tilt head and the lesion area (e.g., the center of the lesion area), i.e., the treatment distance. The vertical telescopic rod connects the housing 2 and the horizontal telescopic rod. The vertical extension or retraction of the vertical telescopic rod drives the horizontal telescopic rod to move in the vertical direction, and then the horizontal telescopic rod drives the camera 7 with a pan-tilt head to move in the vertical direction, thereby adjusting the height of the camera 7 with a pan-tilt head. Figure 4 Both the horizontal and vertical telescopic rods include a telescopic rod processing module, an extension / retraction drive circuit, and a telescopic rod actuator. When the telescopic rod processing module receives a telescopic rod control signal, it determines whether to extend or retract based on the telescopic rod control parameters contained in the signal. Based on this determination, it sends an extension / retraction drive signal to the extension / retraction drive circuit, causing the telescopic rod actuator to extend or retract.

[0027] See also Figure 2 , the device further includes:

[0028] The timer is used to start timing when the spraying function is started and stop timing when the spraying function is stopped, so as to obtain the treatment time of liquid nitrogen cryotherapy.

[0029] The non-contact thermometer is configured to start measuring the temperature of the affected area receiving liquid nitrogen cryotherapy when the spraying function is activated, and to stop measuring the temperature when the spraying function is deactivated. The non-contact thermometer can be fixedly mounted on the side of the treatment nozzle 6 so as to move with the movement of the treatment nozzle 6.

[0030] The control module is used to obtain the first skin lesion image from the camera 7, and determine the skin lesion area of the skin lesion region based on the first skin lesion image, and determine the default treatment distance between the treatment nozzle and the skin lesion region and the default treatment time of liquid nitrogen cryotherapy according to the skin lesion area of the skin lesion region.

[0031] In order to accurately determine the skin lesion area, a reference object, such as a 1 cm*1 cm square sticker, is set near the skin lesion area in advance. In this way, the first skin lesion image not only includes the skin lesion area, but also includes a reference object of known size and area.

[0032] The control module identifies the skin lesion area and the reference object from the first skin lesion image, and counts the number of pixels of the identified skin lesion area and the number of pixels of the reference object, and then determines the skin lesion area of the skin lesion area based on the number of pixels of the skin lesion area, the number of pixels of the reference object, and the known actual area of the reference object. For example, based on the number of pixels of the reference object in the first skin lesion image and the known actual area of the reference object, a correspondence between the number of pixels and the actual area is determined, and the skin lesion area of the skin lesion area is determined based on the number of pixels of the skin lesion area in the first skin lesion image and the correspondence between the number of pixels and the actual area.

[0033] See also Figure 2 The device may further include: a first storage unit for storing a first correspondence table between skin lesion area and treatment distance and a second correspondence table between skin lesion area and treatment time when using treatment nozzles of different specifications, that is, the first and second correspondence tables record the default treatment time and default treatment distance corresponding to different skin lesion areas. The initial default treatment time and default treatment distance can be derived based on expert experience. When sufficient data is accumulated, big data analysis and statistics can be used to derive a treatment time and treatment distance that is more helpful for patient treatment, and the obtained treatment time and treatment distance are used as new default treatment time and new default treatment distance to update the first and second correspondence tables.

[0034] Accordingly, the control module obtains the specifications of the treatment nozzle, and according to the specifications of the treatment nozzle, searches the first correspondence table stored in the first storage unit to find the default treatment distance corresponding to the lesion area of the lesion area, and searches the second correspondence table stored in the first storage unit to find the default treatment time required for using the treatment nozzle when performing liquid nitrogen cryotherapy on the lesion area.

[0035] Furthermore, the control module is also used to control the start of the spraying function. Specifically, before treatment, if the spraying start condition is met, the spraying function is started. For example, the user can manually control the treatment nozzle to align with the skin lesion area (for example, the center of the skin lesion area) and adjust the distance between the treatment nozzle and the skin lesion area based on the default treatment distance. For example, the distance between the treatment nozzle and the skin lesion area is adjusted to the default treatment distance, or fine-tuning is performed on the basis of the default treatment distance, and the distance between the treatment nozzle and the skin lesion area is adjusted to the fine-tuned distance. At this time, the spraying function can be manually started through the touch screen or physical keyboard or physical button. After receiving the instruction to manually start the spraying function, the control module starts the spraying function. For another example, the control module starts the spraying function after controlling the treatment nozzle to align with the skin lesion area (for example, the center of the skin lesion area) and the distance between the treatment nozzle and the skin lesion area reaches a specified distance (that is, reaches the default treatment distance or reaches the distance fine-tuned based on the default treatment distance). In which, the controller can use the camera to aim at the lesion area (for example, the center of the lesion area), and adjust the position of the treatment nozzle according to the relative position relationship between the camera position and the treatment nozzle (especially the relative position between the axis of the camera lens and the nozzle of the treatment nozzle). For example, by utilizing the telescopic function of the connecting mechanism 8 in the horizontal and / or vertical directions, the nozzle of the treatment nozzle is aimed at the lesion area (for example, the center of the lesion area) and reaches a specified distance from the lesion area (for example, the center of the lesion area).

[0036] Furthermore, the control module is also used to control the stopping of the spraying function. In one embodiment, during the treatment process, the spraying function is stopped when at least one spraying stopping condition is met. Wherein, the spraying stopping conditions include: the treatment time reaches or exceeds the default treatment time; the temperature reaches the preset target temperature; the edge of the treated lesion area in the second lesion image coincides with the edge of the lesion area. Wherein, when the treatment time reaches or exceeds the default treatment time, it means that the treatment time has reached the target. Stopping the treatment at this time can reduce the possibility of blistering of the lesion and reduce damage to the surrounding normal skin. When the edge of the treated lesion area in the second lesion image coincides with the edge of the lesion area, it means that the lesion area boundary has been reached. If the treatment is continued, it is likely to damage the surrounding normal skin. Stopping the treatment at this time can reduce damage to the surrounding normal skin. In another embodiment, the medical staff manually stops the spraying function through a touch screen, a physical keyboard, or a physical button according to the actual situation, such as an emergency such as patient discomfort.

[0037] In addition, the control module can also be used to determine the amount of liquid nitrogen (or liquid amount) used for each treatment. Specifically, the amount of liquid used for this treatment is determined based on the specifications of the treatment nozzle and the treatment time.

[0038] In addition, the control module can also be used to determine the depth of the skin lesion. Specifically, before the skin lesion area is subjected to liquid nitrogen cryotherapy, the first distance between the camera lens and the skin lesion area (preferably the center of the skin lesion area) is determined according to the monocular camera ranging method. After the skin lesion area is subjected to liquid nitrogen cryotherapy, the second distance between the camera lens and the treated skin lesion area (preferably the center of the skin lesion area) is determined according to the monocular camera ranging method, and the skin lesion depth is determined based on the first distance and the second distance. As an alternative embodiment, a ranging sensor can be set around the camera lens for ranging, and then the ranging result can be compensated according to the relative position between the ranging sensor and the camera lens (lens axis) to obtain the required distance.

[0039] See also Figure 2 The device may further include: a second storage unit for storing treatment information of each patient including lesion area, lesion depth, default treatment distance, default treatment time, actual treatment time, liquid volume, and a third lesion image, so as to determine treatment depths, treatment distances, treatment times, and liquid volumes suitable for different lesion areas by analyzing the treatment information of multiple patients.

[0040] See also Figure 1 and Figure 2 The device may further include a touch screen, which may be mounted on the top surface of the housing 2. This touch screen is used for displaying, for example, lesion area, lesion depth, default treatment distance, default treatment time, actual treatment time, liquid volume, first lesion image, second lesion image, and third lesion image. It is also used for inputting, for example, specific parameters such as treatment time and treatment distance, commands for controlling the various actuators of the camera and treatment nozzle, starting or stopping the spraying function, starting or stopping camera image acquisition, switching display content, and so on.

[0041] See also Figure 4 The working process of the liquid nitrogen freezing equipment of this embodiment may include:

[0042] Step S100: image acquisition.

[0043] Before liquid nitrogen cryotherapy is performed, the control module controls the pan / tilt head, or the pan / tilt head and the telescopic rod, so that the center of the skin lesion area is located on the optical axis of the camera lens, and the camera lens faces the skin lesion area.

[0044] A reference object of known size and area, such as a circular sticker with a radius of 1 cm, is placed near the lesion area in advance. A camera captures the lesion area to obtain a first lesion image including the lesion area and the reference object.

[0045] Step S200: Calculate the skin lesion area.

[0046] The control module identifies the skin lesion region and the reference object from the first skin lesion image, counts the number of pixels in the identified skin lesion region and the number of pixels in the reference object, and then determines the skin lesion area of the skin lesion region based on the number of pixels in the skin lesion region, the number of pixels in the reference object, and the known actual area of the reference object. For example, a correspondence between the number of pixels and the actual area is determined based on the number of pixels of the reference object in the first skin lesion image and the known actual area of the reference object, and the skin lesion area of the skin lesion region is determined based on the number of pixels in the skin lesion region in the first skin lesion image and the correspondence between the number of pixels and the actual area.

[0047] Step S300: Determine a default treatment time and a default treatment distance for treating the skin lesion according to the skin lesion area.

[0048] The default treatment distance can be determined by:

[0049] In the first embodiment, the control module obtains the specifications of the treatment nozzle, and searches the first correspondence table stored in the first storage unit according to the specifications of the treatment nozzle, finds the default treatment distance corresponding to the lesion area of the lesion area, and uses the default treatment distance as the default treatment distance for this treatment.

[0050] In a second embodiment, after obtaining the default treatment distance through the first correspondence table, the default treatment distance is fine-tuned, and the fine-tuned distance is used as the default treatment distance for this treatment.

[0051] Likewise, the default treatment time can be determined by:

[0052] In a first embodiment, the control module obtains the specifications of the treatment nozzle, and searches the second correspondence table stored in the first storage unit according to the specifications of the treatment nozzle to find the treatment time required for liquid nitrogen cryotherapy of the lesion area as the default treatment time.

[0053] In the second embodiment, after the default treatment time is obtained through the second correspondence table, the default treatment time is fine-tuned, and the fine-tuned time is used as the default treatment distance for this treatment.

[0054] It should be noted that the "time" in the treatment time and default treatment time involved in the present invention refers to "duration", such as 10s, rather than a specific time point, such as 12:15.

[0055] In addition to determining the default treatment distance and default treatment time, this embodiment can further determine the treatment depth and liquid nitrogen amount. For example, a third correspondence table between lesion area and treatment depth and a fourth correspondence table between lesion area and liquid nitrogen amount are pre-stored in the first storage unit. Specifically, the third and fourth correspondence tables record the default treatment depths and default liquid nitrogen amounts corresponding to different lesion areas. The initial default treatment depths and default liquid nitrogen amounts can be based on expert experience. Once sufficient data is accumulated, a treatment depth and liquid nitrogen usage amount that are more conducive to patient treatment can be determined through big data analysis and statistics. The resulting treatment depth and liquid nitrogen usage amount are used as the new default treatment depth and new default liquid nitrogen amount, and the third and fourth correspondence tables are updated.

[0056] Step S400: Start the spraying function to treat skin lesions.

[0057] The control module uses a camera to aim at the lesion area (for example, the center of the lesion area), and then adjusts the position of the treatment nozzle according to the relative position relationship between the camera position and the treatment nozzle, so that the treatment nozzle is aimed at the lesion area (for example, the center of the lesion area). After the treatment nozzle is aimed at the lesion area and the distance from the lesion area reaches the default treatment distance for this treatment, the spraying function is started, and the liquid nitrogen valve on the liquid nitrogen supply pipe is opened to connect the liquid nitrogen container and the treatment nozzle, so that the treatment nozzle sprays liquid nitrogen toward the lesion area.

[0058] Step S500: Stop the spraying function.

[0059] During the liquid nitrogen cryotherapy of the skin lesion area, the control module obtains the treatment time of the liquid nitrogen cryotherapy from the timer, obtains the temperature of the skin lesion area receiving the liquid nitrogen cryotherapy from the non-contact thermometer, and obtains a second skin lesion image from the camera. When at least one of the treatment time, the temperature, and the treated skin lesion area in the second skin lesion image meets the spraying stop condition, the spraying function is stopped. Alternatively, in the event of an emergency such as patient discomfort, the medical staff can manually stop the spraying function at any time, that is, by closing the liquid nitrogen valve on the liquid nitrogen supply pipeline to cut off the passage for transporting liquid nitrogen from the liquid nitrogen container to the treatment nozzle.

[0060] By repeating the above steps S100 to S500, each skin lesion is treated in turn until all skin lesions are treated.

[0061] The present invention provides a liquid nitrogen freezing device that acquires and analyzes images of skin lesions to determine their area. This device then determines parameters such as treatment time, treatment distance, and liquid nitrogen volume based on the lesion area, thereby improving the accuracy of liquid nitrogen cryotherapy. The device also adjusts the position of the treatment nozzle to position the lesion at the optimal center of the treatment at a specified treatment distance, maximizing the quality of liquid nitrogen freezing. During the automatic spraying of liquid nitrogen for cryotherapy, the device stops spraying liquid nitrogen based on at least one of the actual treatment time, the image of the lesion being treated, and the treated area determined through image acquisition and analysis. This entire process not only standardizes the time and distance of lesion treatment but also reduces damage to the surrounding healthy skin, improving the patient's healing rate and overall patient satisfaction. The device is a novel treatment device that integrates positioning, timing, range, and depth control, precise targeting, and adjustable intensity, providing guidance for clinical liquid nitrogen treatment.

[0062] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but are not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and essence of the present invention shall fall within the scope of the present invention.

Claims

1. A liquid nitrogen freezing device, comprising: A treatment nozzle, a liquid nitrogen supply pipeline, a liquid nitrogen valve connected to the liquid nitrogen supply pipeline, and a liquid nitrogen container connected to the treatment nozzle through the liquid nitrogen supply pipeline; Characterized in that the device further comprises: A camera with a pan / tilt head, used to capture a first skin lesion image before liquid nitrogen cryotherapy is performed on the skin lesion area, and to capture a second skin lesion image during the liquid nitrogen cryotherapy of the skin lesion area; a control module, configured to determine the skin lesion area of the skin lesion region based on the first skin lesion image, and determine, based on the skin lesion area, a default treatment distance between the treatment nozzle and the skin lesion region and a default treatment time for the current liquid nitrogen cryotherapy; A timer is used to start timing when the spraying function is activated and stop timing when the spraying function is stopped, so as to obtain the treatment time of the liquid nitrogen cryotherapy; A non-contact thermometer is used to start measuring the temperature of the skin lesion area receiving liquid nitrogen cryotherapy when the spraying function is activated, and to stop measuring the temperature when the spraying function is stopped; Wherein, after the treatment nozzle is aimed at the skin lesion area and the distance from the skin lesion area reaches the default treatment distance, the control module activates the current spraying function, connects the liquid nitrogen container and the treatment nozzle by opening the liquid nitrogen valve on the liquid nitrogen supply pipe, and causes the treatment nozzle to spray liquid nitrogen toward the skin lesion area; During the liquid nitrogen cryotherapy of the lesion area, the control module obtains the treatment time of the liquid nitrogen cryotherapy from the timer, obtains the temperature of the lesion area receiving the liquid nitrogen cryotherapy from the non-contact thermometer, obtains a second lesion image from the camera, and when it is determined based on the treatment time and the default treatment time, the temperature and the preset target temperature, the treated lesion area in the second lesion image, and the lesion area that at least one of the treatment time, the temperature, and the treated lesion area in the second lesion image meets the spraying stop condition, the control module stops the spraying function and cuts off the passage for transporting liquid nitrogen from the liquid nitrogen container to the treatment nozzle by closing the liquid nitrogen valve on the liquid nitrogen supply pipeline.

2. The device according to claim 1, characterized in that The first skin lesion image includes the skin lesion area and a reference object set near the skin lesion area; The control module determining the skin lesion area of the skin lesion region based on the first skin lesion image includes: identifying the skin lesion area and the reference object from the first skin lesion image; Counting the number of pixels of the skin lesion area in the first skin lesion image and the number of pixels of the reference object; The skin lesion area of the skin lesion area is determined according to the number of pixels of the skin lesion area in the first skin lesion image, the number of pixels of the reference object, and the known actual area of the reference object.

3. The device according to claim 2, characterized in that The control module determines a correspondence between the number of pixels and the actual area based on the number of pixels of the reference object in the first skin lesion image and the known actual area of the reference object, and determines the lesion area of the skin lesion area based on the number of pixels of the skin lesion area in the first skin lesion image and the correspondence between the number of pixels and the actual area.

4. The device according to claim 1, characterized in that The device further comprises: The first storage unit is used to store a first correspondence table between skin lesion area and treatment distance and a second correspondence table between skin lesion area and treatment time when using treatment nozzles of different specifications.

5. The device according to claim 4, characterized in that The control module determines, based on the skin lesion area of the skin lesion area, a default treatment distance between the treatment nozzle and the skin lesion area and a default treatment time for the liquid nitrogen cryotherapy treatment, including: searching the first corresponding relationship table stored in the first storage unit to find a treatment distance corresponding to the skin lesion area of the skin lesion region as a default treatment distance; The second corresponding relationship table stored in the first storage unit is searched to find the treatment time required for liquid nitrogen cryotherapy of the skin lesion area as the default treatment time.

6. The device according to claim 1, characterized in that The spraying stop conditions include: The treatment time reaches or exceeds the default treatment time; The temperature reaches a preset target temperature; The edge of the treated skin lesion area in the second skin lesion image coincides with the edge of the skin lesion area.

7. The device according to claim 1, characterized in that The camera is further used to collect a third skin lesion image after the skin lesion area is subjected to liquid nitrogen cryotherapy.

8. The device according to claim 7, characterized in that The control module is further configured to determine the amount of liquid used in the current treatment based on the specifications of the treatment nozzle and the treatment time; And / or, before performing liquid nitrogen cryotherapy on the lesion area, determining a first distance between the camera lens and the center of the lesion area; after performing liquid nitrogen cryotherapy on the lesion area, determining a second distance between the camera lens and the center of the lesion area; and determining the lesion depth based on the first distance and the second distance.

9. The device according to claim 8, characterized in that The device further comprises: The second storage unit is used to store the treatment information of each patient, including the lesion area, lesion depth, default treatment distance, default treatment time, actual treatment time, liquid volume, and a third lesion image, so as to determine the treatment depth, treatment distance, treatment time, and liquid volume suitable for different lesion areas by analyzing the treatment information of multiple patients.

10. The device according to claim 8, characterized in that The device further comprises: The touch screen is used to display the skin lesion area, skin lesion depth, default treatment distance, default treatment time, actual treatment time, liquid volume, first skin lesion image, second skin lesion image and third skin lesion image.

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