Radiotherapy vacuum pad die body air pressure early warning device and radiotherapy vacuum pad die body

Abstract

The utility model relates to the field of radiotherapy vacuum pad medical instruments, and discloses an air pressure early warning device for a radiotherapy vacuum pad die body, which is used for detecting the pressure of an air cavity in the radiotherapy vacuum pad die body and comprises an air pressure sensing module, a signal processing module, an alarm feedback module and a central control unit, the air pressure sensing module detects the air pressure in the air cavity and outputs an analog voltage signal, the signal processing module is electrically connected with the air pressure sensing module and converts the analog voltage signal into a digital air pressure signal, and the alarm feedback module comprises a sound-light alarm unit and a touch screen display interface; the central control unit is electrically connected to the signal processing module, the central control unit is provided with an air pressure threshold range, and if the digital air pressure signal is detected to be outside the air pressure threshold range, the alarm feedback module is controlled to give an alarm. By accurately monitoring the air pressure change in the air cavity of the vacuum pad die body, the body position stability in the treatment process is ensured, and therefore the situation that the body position of a patient is inaccurate or treatment errors are caused by the air pressure problem is avoided.

Description

Technical Field

[0001] This utility model relates to the field of radiotherapy vacuum pad medical devices, specifically to a radiotherapy vacuum pad phantom pressure warning device and a radiotherapy vacuum pad phantom. Background Technology

[0002] Traditional radiotherapy vacuum phantoms are typically made of flexible materials, using a vacuum pump to evacuate air and tightly conform to the patient's body surface, thus stabilizing their position. While this design effectively stabilizes the patient, in practice, vacuum phantoms often suffer from unstable air pressure. Due to factors such as aging of the phantom's materials or connecting components, or poor airtightness, air pressure may leak or drop, causing the phantom to lose sufficient stabilizing force and consequently affecting the stability of the patient's position.

[0003] Furthermore, most vacuum phantoms currently lack real-time pressure monitoring systems. During radiotherapy, pressure changes are often only detected after treatment, by which time the patient's position may have subtly shifted, leading to inaccurate radiation paths. Such pressure leaks are often undetectable visually or tactilely, increasing uncertainty and error during treatment. Existing vacuum phantoms typically rely on radiotherapy personnel manually checking and adjusting the pressure. If pressure changes during treatment, personnel can only manually check the pressure gauge or rely on touch to determine phantom stability. This manual adjustment method is prone to oversights, especially in high-precision treatments, where errors can lead to inaccurate tumor irradiation, affecting treatment outcomes and even posing risks to the patient's health.

[0004] Therefore, there is a lack of an early warning device in the existing technology that can monitor the air pressure status of the vacuum pad mold in real time. Utility Model Content

[0005] The purpose of this invention is to overcome the problem that existing technologies cannot monitor the air pressure status of the vacuum pad phantom in real time and provide early warnings. This invention provides a radiotherapy vacuum pad phantom air pressure early warning device and a radiotherapy vacuum pad phantom. The early warning device can monitor the air pressure status of the vacuum pad phantom in real time and issue an alarm when the air pressure drops to a critical value, thereby preventing patient instability caused by abnormal air pressure.

[0006] To achieve the above objectives, this utility model provides a radiotherapy vacuum pad phantom pressure early warning device for detecting the pressure of the air cavity within the radiotherapy vacuum pad phantom, comprising:

[0007] A pressure sensing module, which detects the pressure inside the air chamber and outputs an analog voltage signal;

[0008] The signal processing module is electrically connected to the pressure sensing module and converts the analog voltage signal into a digital pressure signal;

[0009] An alarm feedback module, comprising an audible and visual alarm unit and a touchscreen display interface; and

[0010] A central control unit, electrically connected to the signal processing module, controls the alarm feedback module to issue an alarm based on the digital air pressure signal provided by the signal processing module.

[0011] Preferably, it further includes a pressure regulating device, which includes a vacuum pump and a gas pipe, one end of which is connected to the vacuum pump, and the other end of which is connected to the gas chamber.

[0012] The central control unit can control the operation of the air pressure regulating device to regulate the air pressure in the air chamber.

[0013] Preferably, the system also includes a touch screen, which is electrically connected to the central control unit. The touch screen is used to display the current air pressure status and alarm prompts in the air chamber, and can be used to control the air pressure in the air chamber.

[0014] Preferably, the pressure sensing module uses a piezoresistive sensor with a range of -50kPa to +50kPa, and the voltage signal output by the piezoresistive sensor is linearly related to the pressure value.

[0015] Preferably, the sensitivity coefficient of the piezoresistive sensor is 0.1V / 1kPa.

[0016] Preferably, the signal processing module includes a low-pass filter circuit and an operational amplifier. The low-pass filter circuit is electrically connected to the operational amplifier. The low-pass filter circuit uses an RC filter with a cutoff frequency of 10Hz. The operational amplifier is configured with a gain of 2 and outputs a digital voltage signal in the range of 0-10V.

[0017] Preferably, the analog-to-digital converter of the central control unit has a sampling rate of at least 860 SPS and a resolution of 1 mV.

[0018] Preferably, the system further includes a redundant power supply module, which is electrically connected to the central control unit and is used to supply power to the central control unit.

[0019] This utility model also provides a radiotherapy vacuum pad phantom, which includes the radiotherapy vacuum pad phantom air pressure warning device as described above.

[0020] Preferably, the radiotherapy vacuum pad phantom further includes an air nozzle for air intake or exhaust, and the radiotherapy vacuum pad phantom is provided with a head filling port corresponding to the patient's head position.

[0021] Based on common technical knowledge in the field, the above-mentioned preferred technical solutions can be freely combined to obtain the preferred embodiments of this application.

[0022] By using the above technical solution, the system ensures the stability of the patient's position during treatment by accurately monitoring the air pressure changes in the air cavity of the vacuum pad phantom. If the air pressure in the air cavity is lower or higher than the set threshold, the system will issue an alarm in a timely manner to remind the operator to check and make necessary adjustments, thereby avoiding inaccurate patient positioning or treatment errors due to air pressure issues and ensuring the stability of the patient's position. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the signal transmission process of the air pressure early warning device for the radiotherapy vacuum pad phantom according to an embodiment of the present invention.

[0024] Figure 2 This is a three-dimensional structural diagram of the radiotherapy vacuum pad according to an embodiment of the present invention.

[0025] Explanation of reference numerals in the attached figures

[0026] 100 Radiotherapy Vacuum Pad Phantom Air Pressure Early Warning Device

[0027] 1 air chamber

[0028] 2. Barometric Pressure Sensor Module

[0029] 3 Signal Processing Module

[0030] 4 Central Control Unit

[0031] 5 Alarm Feedback Module

[0032] 6 head filling port

[0033] 7 Leg filling holes

[0034] 8 valves

[0035] 9. Radiotherapy vacuum pad phantom Detailed Implementation

[0036] In this invention, unless otherwise stated, directional terms such as "upper" generally refer to a higher position relative to a reference plane or object; "lower" generally refers to a lower position relative to a reference plane or object; "left" generally refers to the left side relative to the observer; and "right" generally refers to the right side relative to the observer. "Inner" generally refers to the interior of an object or space, and "outer" generally refers to the exterior of an object or space. "Far" means a greater distance from the observer or a reference point; and "near" means a smaller distance from the observer or a reference point.

[0037] This utility model provides a pressure warning device 100 for a radiotherapy vacuum pad phantom 9, used to detect the pressure of the air cavity 1 inside the radiotherapy vacuum pad phantom 9. The device includes a pressure sensing module 2, a signal processing module 3, an alarm feedback module 5, and a central control unit 4. The pressure sensing module 2 detects the air pressure inside the air cavity 1 and outputs an analog voltage signal. The signal processing module 3 is electrically connected to the pressure sensing module 2 and converts the analog voltage signal into a digital pressure signal. The alarm feedback module 5 includes an audible and visual alarm unit and a touchscreen display interface. The central control unit 4 is electrically connected to the signal processing module 3 and has a pressure threshold range. If the digital pressure signal is detected to be outside the pressure threshold range, the alarm feedback module 5 is controlled to issue an alarm.

[0038] The system ensures patient positioning stability during treatment by precisely monitoring air pressure changes within the air chamber 1 of the vacuum phantom. If the air pressure in chamber 1 falls below or exceeds a set threshold, the system will promptly issue an alarm, alerting the operator to check and make necessary adjustments. This prevents inaccurate patient positioning or treatment errors due to air pressure issues, ensuring patient positioning stability. The alarm feedback module 5 includes an audible and visual alarm unit and a touchscreen display interface, providing multiple feedback methods. The audible and visual alarm quickly attracts the attention of radiation therapy personnel, while the touchscreen display interface shows the air pressure status and related data in real time, facilitating monitoring and adjustments. Automated monitoring and alarm functions reduce reliance on manual checks by radiation therapy personnel, lowering the possibility of human error, especially in high-precision treatments, ensuring treatment accuracy.

[0039] The operator sets the safety air pressure threshold via a touchscreen, and the MCU logic of the central control unit 4 can be:

[0040] If the real-time air pressure value is greater than or equal to the threshold, the display screen will be updated to a green "normal" state.

[0041] If the real-time air pressure value is less than the threshold, the alarm system will be triggered, and the abnormal timestamp will be recorded to the storage chip (such as EEPROM).

[0042] The MCU can control the buzzer (frequency 2kHz, duty cycle 50%) via the PWM pin, and the drive circuit uses an NPN transistor (such as 2N3904) to amplify the current.

[0043] The normal state of the visual alarm is a solid green light (GPIO output high level). When an abnormality is detected, it can flash red (GPIO output 1Hz square wave), and the touch screen pop-up window will display "Abnormal air pressure! Current value: XX kPa" and handling suggestions.

[0044] In a preferred embodiment, the radiotherapy vacuum pad phantom air pressure warning device 100 further includes an air pressure regulating device, which includes a vacuum pump and an air pipe. One end of the air pipe is connected to the vacuum pump, and the other end of the air pipe is connected to the air chamber 1. The central control unit 4 can control the operation of the air pressure regulating device to regulate the air pressure in the air chamber 1.

[0045] Specifically, when the central control unit 4 issues an adjustment command, the vacuum pump starts and adjusts the air pressure in the air chamber 1 to within the air pressure threshold range. This automated adjustment mechanism reduces the need for manual intervention and improves operational convenience. Combined with air pressure monitoring and adjustment functions, the system can react quickly when abnormal air pressure is detected. By monitoring air pressure in real time and automatically adjusting it, the system ensures that the patient's position remains stable throughout radiotherapy, reducing treatment risks caused by air pressure fluctuations. It effectively avoids positional shifts or instability due to insufficient air pressure, ensuring that the radiation beam accurately irradiates the tumor lesion area during radiotherapy, reducing treatment errors caused by positioning issues, and improving the safety and effectiveness of treatment.

[0046] In a preferred embodiment, the air pressure warning device 100 for the radiotherapy vacuum pad phantom also includes a touch screen electrically connected to the central control unit 4. The touch screen displays the current air pressure status and alarm prompts within the air chamber 1, and can be used to control the air pressure within the air chamber 1. The touch screen can display the air pressure status within the air chamber 1 in real time, including the current air pressure value, air pressure threshold range, and whether it is in normal operating condition. This intuitive display allows radiotherapy personnel to quickly understand the equipment's operating status, facilitating timely judgment and adjustments. The touch screen not only displays the air pressure status but also provides alarm prompts. When the air pressure exceeds the set threshold range, the touch screen will issue visual and audible alarms to remind radiotherapy personnel to pay attention to the air pressure change. Through the touch screen, radiotherapy personnel can conveniently control the air pressure within the air chamber 1. For example, personnel can directly input the required air pressure value on the touch screen, and the central control unit 4 will automatically adjust the air pressure according to the instruction. This convenient control method improves operational flexibility and reduces the complexity of manual adjustments.

[0047] Among its features, the automated air pressure monitoring and early warning function simplifies the traditional process of manually checking air pressure during treatment. Operators only need to check and adjust according to the alarm prompts, avoiding treatment deviations caused by human error and improving the efficiency and accuracy of the treatment process.

[0048] In a preferred embodiment, the pressure sensing module 2 employs a piezoresistive sensor with a range of -50 kPa to +50 kPa, such as a high-precision piezoresistive pressure sensor (e.g., the MPX5700 series). When the pressure inside the vacuum pad mold changes, the pressure-sensitive diaphragm inside the sensor deforms, causing the Wheatstone bridge to become unbalanced. Its output is a voltage signal proportional to the pressure. The voltage signal output by the piezoresistive sensor is linearly related to the pressure value, and it can adapt to various pressure conditions. Its measurement range enables the sensor to effectively monitor the pressure changes inside the air chamber 1, providing accurate measurement results regardless of whether it is under negative or positive pressure.

[0049] In a preferred embodiment, the piezoresistive sensor has a sensitivity coefficient of 0.1V / 1kPa, enabling it to provide accurate air pressure readings. This allows the signal processing module 3 to more accurately convert the analog voltage signal into a digital air pressure signal. This accuracy helps ensure timely detection of air pressure abnormalities during treatment, allowing for appropriate measures to be taken. This feedback precision helps improve the safety of the radiotherapy process and ensures the stability of the patient's position.

[0050] The air pressure calibration of the central control unit 4 includes:

[0051] Air pressure value (kPa) = (ADC original value / 4096 × 10V - offset voltage) × sensitivity coefficient;

[0052] The offset voltage and sensitivity coefficient are calibrated by the sensor at the factory. The raw ADC value represents the digital quantity after the analog voltage signal output by the pressure sensing module 2 is discretized by the ADC (analog-to-digital converter) chip. The ADC chip can be a 12-bit high-precision analog-to-digital converter (such as ADS1115), with a sampling rate of 860 SPS (samples per second) and a resolution of up to 1mV. The MCU (such as STM32F103) of the central control unit 4 connects to I... 2 The C-bus controls the ADC chip, converting the amplified analog voltage signal into a digital signal.

[0053] In a preferred embodiment, the signal processing module 3 includes a low-pass filter circuit and an operational amplifier. The low-pass filter circuit is electrically connected to the operational amplifier and employs an RC low-pass filter with a cutoff frequency of 10Hz, which can effectively suppress high-frequency noise and interference signals. The operational amplifier is configured to use an instrumentation amplifier (such as AD620) at twice the gain to improve the signal-to-noise ratio and ensure that subtle air pressure changes can be effectively detected. The amplification gain and the output digital voltage signal range of 0-10V ensure that subtle air pressure changes can be amplified to a usable voltage range, ensuring that the signal has sufficient amplitude in subsequent processing and display. This is crucial for ensuring that the system can accurately reflect the air pressure changes within the air chamber 1. The digital voltage signal output by the operational amplifier, with a range of 0-10V, is suitable for connection and interaction with subsequent central control unit 4 and touch screen devices, ensuring that the signal can be effectively transmitted and processed, facilitating real-time monitoring and control.

[0054] The signal processing module 3 consists of a low-pass filter circuit and an instrumentation amplifier, which performs noise cancellation and amplitude amplification on the analog voltage signal.

[0055] In a preferred embodiment, the analog-to-digital converter of the central control unit 4 has a sampling rate of at least 860 SPS and a resolution of 1 mV. The high sampling rate ensures that the system can capture rapid changes in air pressure within the air chamber 1 in real time, especially during radiotherapy, where air pressure may fluctuate rapidly due to various factors. The high sampling rate also helps improve the system's response speed to air pressure changes, ensuring timely detection and handling of air pressure anomalies. The 1 mV resolution enables the detection of voltage changes of at least 1 mV, allowing the system to accurately reflect minute air pressure changes within the air chamber 1, ensuring accurate air pressure monitoring and improving positional stability during radiotherapy.

[0056] In a preferred embodiment, the radiotherapy vacuum pad phantom air pressure warning device 100 further includes a redundant power supply module, which is electrically connected to the central control unit 4 and is used to supply power to the central control unit 4.

[0057] Specifically, the power management chip (such as TPS3809) monitors the main power supply voltage in real time. When the main power supply voltage of the central control unit 4 is lower than 4.5V, the redundant power supply module is electrically connected to the central control unit 4, and the redundant power supply module switches to the backup power supply to power the central control unit 4. The backup power supply prioritizes maintaining the power supply to the MCU and alarm system, ensuring that the alarm can continue for at least 30 minutes after a power outage.

[0058] In another aspect, this utility model also provides a radiotherapy vacuum pad phantom 9, which includes the aforementioned radiotherapy vacuum pad phantom air pressure warning device 100. The radiotherapy vacuum pad phantom 9 also includes an air nozzle 8 for air intake or exhaust. The air nozzle 8 allows for convenient gas intake and exhaust of the radiotherapy vacuum pad phantom 9, enabling radiotherapy personnel to quickly adjust the air pressure within the air chamber 1 as needed, ensuring a close fit between the phantom and the patient's body surface, thereby improving treatment accuracy. Through the air nozzle 8, radiotherapy personnel can easily inflate or de-inflate the air chamber 1. Combined with the real-time monitoring function of the air pressure warning device, it can quickly respond to air pressure changes, simplifying the operation process and improving work efficiency.

[0059] In a preferred embodiment, such as Figure 2 As shown, the radiotherapy vacuum pad phantom 9 has a head filling port 6 corresponding to the patient's head position. The radiotherapy vacuum pad phantom 1 has a leg filling groove corresponding to the patient's legs position. Both the leg filling groove and the head filling groove are built into the front and rear ends of the vacuum pad, forming the head filling port 6 at one end of the vacuum pad and the leg filling port 7 on the other side. The leg filling groove and the head filling groove can be filled with plastic foam or inflatable bags. According to the degree of the patient's body curvature, the legs and head can be filled to the corresponding height. After the legs and head positions corresponding to the patient are raised on the negative pressure vacuum pad, the patient with a bent body can lie flat on the negative pressure vacuum pad, which can keep the body position consistent during radiotherapy and improve the radiotherapy effect.

[0060] Specifically, the main material of the radiotherapy vacuum pad phantom 9 is medical-grade silicone or PVC, which has good softness and plasticity and can maintain a stable shape under low air pressure. The high-temperature resistance of the material allows it to withstand the heat generated during CyberKnife treatment. To ensure patient comfort, the surface is smoothed and covered with an antibacterial coating. The standard dimensions of the radiotherapy vacuum pad phantom 9 are: width 400mm, length 800mm, and thickness 50mm. The dimensions can be customized according to the patient's body shape to ensure that the patient can maintain a comfortable and stable position during treatment. The phantom has a uniform pore structure inside, which can evenly distribute air pressure to ensure the stability of the patient's position. The radiotherapy vacuum pad phantom 9 has multiple air chambers 1, each connected by an air tube. The air pressure in the air chamber 1 can be adjusted according to actual needs. The air chamber 1 uses reinforced silicone material with high pressure resistance to prevent deformation when the air pressure is too low, which would affect the stability of the patient's position.

[0061] The central control unit 4 employs an embedded microcontroller (such as the STM32 series) to monitor air pressure data in real time and compare it with alarm thresholds. The microcontroller also controls the operation of the air pressure regulating device, ensuring timely adjustments in case of abnormal air pressure. The air pressure regulating system uses an electric vacuum pump capable of precisely regulating the air pressure in the internal air chamber 1 of the radiotherapy vacuum pad phantom 9. The electric pump is connected to the control system via an interface; when the control system issues an adjustment command, the electric pump automatically starts and adjusts the air pressure to the set range. This system uses an intelligent adjustment algorithm to automatically adjust the working state of the vacuum pump based on real-time air pressure conditions.

[0062] The equipment is equipped with an LCD touchscreen that displays the current air pressure status and alarm prompts. Treatment personnel can view air pressure data in real time through this interface and adjust the air pressure via the touchscreen when it exceeds the set range. The system supports switching between manual and automatic modes to ensure flexibility in different operating environments.

[0063] During use, connect the pressure sensor, electric vacuum pump, control system, LCD screen, and other components according to the design requirements, ensuring electrical connections between components and reliable sealing between pipes and sensors. All electrical components are housed in a waterproof and dustproof enclosure to prevent contamination in the treatment environment.

[0064] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings; however, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately. However, these simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A radiotherapy vacuum cushion mold air pressure early warning device (100) for detecting the pressure of an air cavity (1) in a radiotherapy vacuum cushion mold (9), characterized in that, It comprises: an air pressure sensing module (2) that detects the air pressure in the air cavity (1) and outputs an analog voltage signal; a signal processing module (3) that is electrically connected to the air pressure sensing module (2) and converts the analog voltage signal into a digital air pressure signal; an alarm feedback module (5) that contains an audible and visual alarm unit and a touch screen display interface; and a central control unit (4) that is electrically connected to the signal processing module (3) to control the alarm feedback module (5) to issue an alarm according to the digital air pressure signal provided by the signal processing module (3).

2. The radiotherapy vacuum cushion mold air pressure early warning device (100) according to claim 1, characterized in that, It also comprises an air pressure regulating device, which includes a vacuum pump and an air pipe, one end of the air pipe being connected to the vacuum pump and the other end of the air pipe being connected to the air cavity (1), wherein the central control unit (4) can control the operation of the air pressure regulating device to regulate the air pressure in the air cavity (1).

3. The radiotherapy vacuum cushion mold air pressure early warning device (100) according to claim 1 or 2, characterized in that, It also comprises a touch screen that is electrically connected to the central control unit (4), the touch screen being used to display the current air pressure state in the air cavity (1) and alarm prompts, and the touch screen being able to be used to control the air pressure in the air cavity (1).

4. The radiotherapy vacuum cushion mold air pressure early warning device (100) according to claim 1 or 2, characterized in that, The air pressure sensing module (2) uses a pressure resistance sensor with a range of -50kPa to +50kPa, and the voltage signal output by the pressure resistance sensor has a linear relationship with the air pressure value.

5. The radiotherapy vacuum cushion mold air pressure early warning device (100) according to claim 4, characterized in that, The sensitivity coefficient of the pressure resistance sensor is 0.1V / 1kPa.

6. The radiotherapy vacuum cushion mold air pressure early warning device (100) according to claim 1 or 2, characterized in that, The signal processing module (3) includes a low-pass filter circuit and an operational amplifier, the low-pass filter circuit being electrically connected to the operational amplifier, the low-pass filter circuit using an RC filter with a cutoff frequency of 10Hz, and the operational amplifier being configured with a gain of 2 and outputting a digital voltage signal with a range of 0-10V.

7. The radiotherapy vacuum cushion mold air pressure early warning device (100) according to claim 1 or 2, characterized in that, The analog-to-digital converter of the central control unit (4) has a sampling rate of at least 860SPS and a resolution of 1mV.

8. The radiotherapy vacuum cushion mold air pressure early warning device (100) according to claim 1 or 2, characterized in that, It also comprises a redundant power supply module that is electrically connected to the central control unit (4) and is used to supply power to the central control unit (4).

9. A radiotherapy vacuum cushion phantom, characterized in that, The radiotherapy vacuum pad mold (9) comprises the radiotherapy vacuum pad mold air pressure warning device (100) according to any one of claims 1-8.

10. The radiotherapy vacuum cushion mold of claim 9, wherein, The radiotherapy vacuum pad mold (9) also comprises an air nozzle (8) for air intake or air exhaust, and the radiotherapy vacuum pad mold (9) is provided with a head filling port (6) corresponding to the position of the patient's head.

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