A system for monitoring intracavitary pressure in biological bodies

Abstract

This invention discloses a system for monitoring intracavitary pressure in a biological organism. A first measuring device for measuring internal pressure and temperature is implanted within the organism's intracavitary cavity, while a second measuring device for measuring external pressure and temperature is positioned adjacent to the organism's external cavity. The two measuring devices can transmit data via an induction coil, allowing the second measuring device to acquire the measurement data from the first device. After calibration and interpolation, the relative pressure value within the organism's intracavitary cavity is obtained. Therefore, this invention requires only a single surgical procedure to implant the measuring device, eliminating the need for a fistula and overcoming difficulties in hygiene maintenance. It does not require the organism to be in a specific environment, and the organism can move freely. Furthermore, it offers high measurement accuracy and allows for continuous monitoring over extended periods.

Description

Technical Field

[0001] This utility model relates to the field of medical devices, and specifically to a system for monitoring intracavitary pressure in biological bodies. Background Technology

[0002] The continuous measurement and long-term monitoring of pressure in biological cavities (especially in the human body) has significant clinical value. For example, continuous monitoring of intracranial pressure provides crucial data for accurately assessing changes in intracranial pressure caused by space-occupying lesions such as intracranial tumors, intracranial trauma, intracranial hemorrhage, and cerebral edema, providing a basis for diagnosis, drug intervention, and treatment to control intracranial pressure. Normal intraocular pressure is fundamental for maintaining the normal shape of the eye and good vision. High intraocular pressure can lead to optic nerve damage, further resulting in glaucoma and even retinal detachment; therefore, continuous monitoring of patients' intraocular pressure is also necessary. Bladder pressure reflects the host's bladder storage capacity. Monitoring data on bladder pressure can be used to diagnose diseases and assess postoperative recovery to prevent urinary difficulties and retention.

[0003] Current technologies for continuous monitoring of intracranial pressure typically require a fistula, through which a pressure-sensitive device is placed. This device simultaneously senses the pressure difference between the internal and external cavities, such as a fluid column representing intracranial and bladder pressure. Intraocular pressure measurement, due to the extremely small size of the target space and its sensitivity, is more often performed using non-contact methods involving air inhalation. Fistula creation requires excellent hygiene to prevent infection and places stringent requirements on the target and environment, such as necessitating an intensive care unit (ICU) setting. Even so, the duration of continuous intracranial pressure monitoring is very short, usually only a few days, making it unsuitable for long-term outpatient monitoring (one publicly reported example is 30 hours).

[0004] Therefore, how to improve the pressure monitoring technology of existing technologies and avoid the difficulties of fistula in terms of limiting the measurement objects, difficulty in hygiene maintenance, and inability to monitor continuously for a long time has become a technical problem that needs to be solved. Utility Model Content

[0005] In view of this, the present invention provides a system for monitoring intracavitary pressure in biological organisms. It requires only one surgery to implant the measuring device into the cavity, eliminating the need for fistula creation, thus overcoming the difficulties in hygiene maintenance. It does not require the organism to be in a specific environment, and the organism can move freely. In addition, it has high measurement accuracy and can monitor continuously for a long time.

[0006] A system for monitoring intracavitary pressure in biological bodies, comprising:

[0007] A first measuring device implanted in the cavity of a biological organism and a second measuring device outside the biological organism.

[0008] The first measuring device includes a first absolute pressure sensor, a first temperature sensor, and a first coil antenna.

[0009] The first absolute pressure sensor is used to measure the first absolute pressure value pi of the biological cavity; the first temperature sensor is used to measure the first temperature value ti of the biological cavity; and the first coil antenna is used to receive control signals, measure pressure and temperature, and transmit the measured pressure and temperature values.

[0010] The second measuring device includes a second absolute pressure sensor, a second temperature sensor, and a second coil antenna.

[0011] The second absolute pressure sensor is used to measure the second absolute pressure value pe of the environment in which the organism is located; the second temperature sensor is used to measure the second temperature value te of the environment in which the organism is located; and the second coil antenna is used to electromagnetically couple with the first coil antenna to send control signals, so that the first measuring device performs temperature and pressure measurements and sends the measured pressure and temperature values.

[0012] The distance between the first absolute pressure sensor and the second absolute pressure sensor is within a set threshold range;

[0013] The monitoring system uses the first absolute pressure value pi and the first temperature value ti inside the biological cavity, and the second absolute pressure value pe and the second temperature value te of the biological environment, combined with the stored calibration data, to obtain the relative pressure value inside the biological cavity.

[0014] Optionally, the threshold range is smaller than the atmospheric elevation difference corresponding to the lowest pressure resolution of the first absolute pressure sensor and the second absolute pressure sensor.

[0015] Optionally, the first absolute pressure sensor and the first temperature sensor form a pair of paired sensors, and the second absolute pressure sensor and the second temperature sensor form another pair of paired sensors.

[0016] Optionally, the second measuring device controls the electromagnetic coupling between the first coil antenna and the second coil antenna to supply power to the first measuring device.

[0017] Optionally, the first measuring device includes a first coil antenna, a first power supply, a first controller, a first absolute pressure sensor, and a first temperature sensor;

[0018] The first coil antenna is used for wireless signal transmission and wireless charging.

[0019] The first power supply is used to condition the received power signal into the power signal required for the operation of the first controller, the first absolute pressure sensor, and the first temperature sensor.

[0020] The first controller is used to receive control signals from the second measuring device and control the first absolute pressure sensor and the first temperature sensor to perform data acquisition, calculation and transmission.

[0021] The first temperature sensor is used to measure the first temperature.

[0022] The first absolute pressure sensor includes: a first absolute pressure sealed cavity, a first open cavity, and a first pressure-sensitive element located between the two. The first pressure-sensitive element is located in the pressure range of the first absolute pressure sealed cavity away from the object being measured. The first open cavity faces the area where the pressure needs to be measured. The first pressure-sensitive element is used to convert the pressure difference between the absolute pressure cavity and the open cavity into an electrical signal suitable for measurement.

[0023] The first absolute pressure sensor further includes a first conditioning and analog-to-digital conversion circuit for powering the first pressure-sensitive element and the first temperature sensor, and for obtaining the measured pressure and temperature signals and transmitting them to the first controller.

[0024] Optionally, the second measuring device includes a second coil antenna, a second power supply, a second controller, a wireless transceiver unit, a communication unit, a second absolute pressure sensor, and a second temperature sensor;

[0025] The second coil antenna is used for wireless signal transmission and wireless charging.

[0026] The second power source is used to power the equipment of the second measuring device;

[0027] The second controller is used to control the various components of the second measuring device and send control signals to the first measuring device.

[0028] The wireless transceiver unit is connected to the second coil antenna via a cable and is used for transmitting and receiving electrical power, control signals, and measurement data.

[0029] The second temperature sensor is used to measure the second temperature of the organism's environment.

[0030] The second absolute pressure sensor includes: a second absolute pressure sealed cavity, a second open cavity, and a second pressure-sensitive element located between the two. The second pressure-sensitive element is located in the pressure range of the second absolute pressure sealed cavity away from the object being measured. The second open cavity faces the area where the pressure needs to be measured. The second pressure-sensitive element is used to convert the pressure difference between the absolute pressure cavity and the open cavity into an electrical signal suitable for measurement. A pressure guide hole is used to connect atmospheric pressure to the second open cavity.

[0031] Optionally, the second absolute pressure sensor further includes a second conditioning and analog-to-digital conversion circuit for powering the second pressure-sensitive element and the second temperature sensor, and for obtaining the measured pressure and temperature signals and transmitting them to the second controller;

[0032] It also includes a communication unit for connecting to a relay device via wired or wireless communication, so that users can easily obtain the corresponding temperature and pressure data, as well as the calculated relative pressure value.

[0033] Therefore, this utility model has the following advantages:

[0034] 1. A first measuring device and a second measuring device are respectively set on the inside and outside of the organism. Only one surgery is needed to implant the first measuring device into the cavity, eliminating the need for fistula creation, overcoming the problem of difficult hygiene maintenance, eliminating the need for the organism to be in a specific environment, and allowing the organism to move freely.

[0035] 2. The first measuring device can be wirelessly powered by the wireless coil of the second measuring device, extending the power supply time and expanding the power supply mode, so that the first measuring device can continuously measure the internal pressure and perform long-term continuous monitoring.

[0036] 3. By using absolute pressure and temperature sensors and calibration data to calibrate temperature and pressure, temperature-independent calibrated intracavitary pressure values ​​and pressure differences are obtained, thereby improving overall measurement accuracy and obtaining high-precision intracavitary pressure values.

[0037] 4. Pressure and temperature sensors can be managed and paired using unique codes, improving calibration accuracy. Attached Figure Description

[0038] The above and other objects, features and advantages of the present invention will become clearer from the following description of embodiments of the present invention with reference to the accompanying drawings, in which:

[0039] Figure 1 This is a schematic diagram of the structure of a system 100 for monitoring intracavitary pressure in a biological body according to a specific embodiment of the present invention;

[0040] Figure 2 This is a schematic diagram of a first measuring device 102 implanted in the internal cavity of a biological body in a system for monitoring pressure in the internal cavity of a biological body according to a specific embodiment of the present invention.

[0041] Figure 3 This is a schematic diagram of a second measuring device 103 located outside the organism in a system for monitoring intracavitary pressure in a biological body according to a specific embodiment of the present invention.

[0042] Figure 4 This is a schematic diagram illustrating the calibration of the system for monitoring intracavitary pressure in biological bodies according to a specific embodiment of the present invention.

[0043] The technical features referred to by the reference numerals in the figure are as follows:

[0044] 100. A system for monitoring intracavitary pressure in biological bodies; 101. Cranial cavity; 102. First measuring device; 103. Second measuring device; 201. Calibration device container; 202. Calibration control system; 203. Data receiving and processing unit; 301. First coil antenna; 302. First power supply; 303. First controller; 304. First conditioning and analog-to-digital conversion circuit; 305. First absolute pressure sealed cavity; 306. First open cavity; 307. Pressure guide tube; 308. First pressure sensitive element; 309. First temperature sensor; 310. First absolute pressure sensor; 401. Second coil antenna; 402. Second power supply; 403. Second controller; 404. Second conditioning and analog-to-digital conversion circuit; 405. Second absolute pressure sealed cavity; 406. Second open cavity; 407. Pressure guide hole; 408. Second pressure sensitive element; 409. Second temperature sensor; 410. Second absolute pressure sensor; 411. Cable; 412. Wireless transceiver unit; 413. Relay device; 414. Communication unit; 415. Local power supply; 416. External power supply unit. Detailed Implementation

[0045] The present application is described below based on embodiments, but it is not limited to these embodiments. In the detailed description of the present application below, certain specific details are described in detail. Those skilled in the art can fully understand the present application without these details. To avoid obscuring the substance of the present application, well-known methods, processes, flows, elements, and circuits are not described in detail.

[0046] Furthermore, those skilled in the art should understand that the accompanying drawings provided herein are for illustrative purposes only and are not necessarily drawn to scale.

[0047] Furthermore, it should be understood that in the following description, "circuit" refers to a conductive loop consisting of at least one element or sub-circuit connected by electrical or electromagnetic connections. When an element or circuit is said to be "connected" to another element or "connected" between two nodes, it can be directly coupled or connected to another element, or there may be intermediate elements. The connection between elements can be physical, logical, or a combination thereof. Conversely, when an element is said to be "directly coupled to" or "directly connected" to another element, it means that there are no intermediate elements between them.

[0048] Unless the context explicitly requires it, words such as "including" or "contains" throughout the application should be interpreted as including rather than exclusive or exhaustive; that is, meaning "including but not limited to".

[0049] In the description of this application, it should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0050] As mentioned earlier, continuous monitoring and measurement (synonymous with "monitoring," the two terms are used interchangeably below) of intracavitary pressures in living organisms, such as intracranial pressure, intraocular pressure, and bladder pressure, are clinically significant. For the human body, the pressure obtained from intracavitary pressure measurements is generally the pressure difference between the intracavitary pressure and the atmospheric pressure at the body's location. From a strict physics perspective, the pressure within a living organism's cavity is actually the pressure difference between the body and the nearby external atmospheric pressure, measured in Pascals (Pa). In the field of medical measurement, pressure measurement is conventionally referred to as "pressure measurement," therefore, pressure will be used to express this physical concept, but the unit will be Pa. Living organisms include humans and animals; the following description uses humans as an example. Those skilled in the art will understand that the technical solutions disclosed in this invention can also be applied to animals, such as for medical experiments, pet treatment, etc.

[0051] Common characteristics of pressure in various cavities of the human body include:

[0052] 1. The pressure range is narrow. For example, the normal range for intraocular pressure is 1.33–2.80 kPa; the normal range for intracranial pressure is 0.5–3.0 kPa, equivalent to the pressure generated by a 30 cm column of water; the upper limit of bladder pressure is slightly higher, with a normal high value not exceeding 4 kPa, equivalent to the pressure of a 40 cm column of water. Generally, solid-state pressure sensors are in a dead zone with no response within this pressure range, or they may show output changes but with low resolution.

[0053] 2. The pressure sensor needs to sense changes in pressure both inside the body and in the adjacent external environment. In other words, this pressure difference is the internal pressure value that needs to be measured and monitored.

[0054] This invention provides a system for monitoring intracavitary pressure in biological organisms. A first measuring device for measuring internal pressure and temperature is implanted within the intracavitary cavity, while a second measuring device for measuring external pressure and temperature is positioned adjacent to the organism outside the cavity. The two measuring devices can transmit data via an induction coil, allowing the second measuring device to acquire the measurement data from the first device. After calibration and interpolation, the relative pressure value within the intracavitary cavity is obtained. Therefore, this system for monitoring intracavitary pressure in biological organisms requires only a single surgical procedure to implant the measuring device, eliminating the need for a fistula and overcoming difficulties in hygiene maintenance. It does not require the organism to be in a specific environment, and the organism can move freely. Furthermore, it offers high measurement accuracy and allows for continuous monitoring over extended periods.

[0055] For details, see Figure 1-3 The illustration shows a system 100 for monitoring intracavitary pressure in a biological body according to a specific embodiment of the present invention, and a corresponding first measuring device 102 and a second measuring device 103.

[0056] The pressure monitoring system 100 includes a first measuring device 102 implanted in the cavity of a biological organism and a second measuring device 103 located outside the biological organism.

[0057] The first measuring device 102 includes a first absolute pressure sensor 310, a first temperature sensor 309, and a first coil antenna 301.

[0058] The first absolute pressure sensor 310 is used to measure the first absolute pressure value pi of the biological cavity, the first temperature sensor 309 is used to measure the first temperature value ti of the biological cavity, and the first coil antenna 301 is used to receive control signals, measure pressure and temperature, and send the measured first absolute pressure value and first temperature value.

[0059] The second measuring device 103 includes a second absolute pressure sensor 410, a second temperature sensor 409, and a second coil antenna 401.

[0060] The second absolute pressure sensor 410 is used to measure the second absolute pressure value (i.e., atmospheric pressure value) pe of the environment where the organism is located; the second temperature sensor 409 is used to measure the second temperature value te of the environment where the organism is located; and the second coil antenna 401 is used to electromagnetically couple with the first coil antenna 301 to send control signals so that the first measuring device 102 performs temperature and pressure measurements and sends the measured pressure and temperature values.

[0061] The distance between the first absolute pressure sensor 310 and the second absolute pressure sensor 410 is within a set threshold range;

[0062] The monitoring system, such as the second measuring device 103, or the first measuring device 102 and the second measuring device 103 together, through their own controller, uses the first absolute pressure value pi and the first temperature value ti inside the biological cavity, and the second absolute pressure value (i.e., atmospheric pressure value) pe and the second temperature value te of the biological environment, combined with the stored calibration data, to obtain the relative pressure value inside the biological cavity.

[0063] At sea level, atmospheric pressure changes by 0.001 kPa for every 10 cm increase in altitude. The distance between the first absolute pressure sensor 310 and the second absolute pressure sensor 410 should be less than the atmospheric elevation difference corresponding to the lowest pressure resolution to ensure measurement accuracy. Taking a minimum pressure resolution of 0.002 kPa as an example, with an atmospheric elevation difference of 20 cm, the distance between the two pressure sensors during calibration and use should not exceed 20 cm. That is, the threshold range for the distance between the second absolute pressure sensor 410 and the first absolute pressure sensor 310 is set to 20 cm.

[0064] In this invention, the second measuring device 103 can be configured to control the electromagnetic coupling between the first coil antenna 301 and the second coil antenna 401 to transmit data between the first measuring device 102 and the second measuring device 103. This includes sending a control signal to the first measuring device 102, measuring a first absolute pressure value pi and a first temperature value ti, and transmitting the measured pressure and temperature values ​​to the second measuring device 103. To increase measurement accuracy, the second measuring device 103 of this invention synchronously acquires the second absolute pressure value (i.e., atmospheric pressure value) pe and the second temperature value te with the first measuring device 102.

[0065] Therefore, this invention can obtain the changes in pressure inside the body and the adjacent external body, as well as the temperature value at the same time, and measure the pressure difference between the body and the external body, i.e., the relative pressure difference, through the above changes.

[0066] Since pressure is greatly affected by temperature, in order to improve the measurement accuracy, this invention measures temperature at the same time as pressure. Using pre-obtained calibration data, the measured temperature and pressure are calibrated to obtain the calibrated temperature and calibrated pressure, thereby obtaining the calibrated pressure difference, which is the relative pressure value required by this invention.

[0067] That is, this utility model only requires one surgery to implant the measuring device into the cavity, without the need for fistula creation, overcoming the problem of difficult hygiene maintenance, without requiring the organism to be in a specific environment, and the organism can move freely; in addition, the measurement accuracy is high and it can be continuously monitored for a long time.

[0068] The second measuring device 103 can be connected to a computer, smart tablet, smartphone, or other device via wired or wireless means, enabling users to obtain relevant intermediate data and results, including calculating the relative pressure value inside the biological cavity for further processing.

[0069] Furthermore, the second measuring device 103 controls the electromagnetic coupling between the first coil antenna 301 and the second coil antenna 401 to supply power to the first measuring device 102. Therefore, the first measuring device 102 can operate without a power source and work in the body for a long time, enabling continuous monitoring and reducing the overall weight.

[0070] However, it is obvious that the first measuring device 102 itself can also have a power source, such as the power supply methods commonly used in the prior art, and can be supplemented by wireless power supply from the first coil wire 301 and the second coil antenna 401. All of the above power supply methods are within the protection scope of this utility model.

[0071] See Figure 1 This illustrates a specific example of the system 100 for monitoring intracavitary pressure in a living organism being fixed in the body. For example, when measuring intracranial pressure in a human skull, a piece of skull can be surgically removed from the skull, and a pit suitable for fixing the implanted measuring device 102 can be ground out on the inner side of the skull. The implanted measuring device 102 is then fixed on the inner side of the skull, and the skull is then fixed to the original removal site using bone cement.

[0072] Other internal cavities of the organism can also be fixed to the cavity walls using other postoperative fixation methods (e.g., using surgical sutures). For example, the second absolute pressure sensor 410 can be fixed to the circuit board of the second measuring device 103, or it can be fixed to the structure of the second coil antenna 401 and connected to the circuit board of the second measuring device 103 via a cable. In this invention, regardless of where the second absolute pressure sensor 410 is fixed, the distance between the second absolute pressure sensor 410 and the first absolute pressure sensor 310 must be less than the atmospheric elevation difference corresponding to the lowest pressure resolution to ensure measurement accuracy.

[0073] To further improve the accuracy of the test, the first measuring device 102 and the second measuring device 103 of this invention use the same type of pressure sensor and temperature sensor.

[0074] Furthermore, the first absolute pressure sensor 310 and the second absolute pressure sensor 410 are the same type of high-resolution absolute pressure sensors, and further, they are sensors with a built-in reference pressure chamber. Using absolute pressure sensors for internal cavity pressure measurement can avoid the response dead zone of sensitive elements in the low-pressure area being measured, resulting in better test sensitivity and resolution.

[0075] Furthermore, as mentioned above, atmospheric pressure on the human body surface varies with air temperature, humidity, altitude, and atmospheric density. For example, the atmospheric pressure at the same point from morning to night can vary by as much as 0.4 kPa, and for every 100 meters change in altitude, the atmospheric pressure changes by approximately 1.1 kPa. The pressure in the reference pressure chamber of the internal pressure sensor also changes with body temperature. Simply using an absolute pressure sensor cannot obtain valuable information about the internal cavity pressure of the human body. Therefore, before the first measuring device is implanted into the body, this invention further utilizes a calibrator (also called a calibration device) to calibrate the first absolute pressure sensor, the first temperature sensor, the second absolute pressure sensor, and the second temperature sensor within the temperature and pressure range where the measuring device operates. This calibrates the pressure and temperature values ​​measured by the calibrator, the first absolute pressure sensor, the first temperature sensor, the second absolute pressure sensor, and the second temperature sensor under different temperatures and pressures. This calibrated data allows for the calculation of intracranial pressure using real-time measurement data combined with the calibration data from the paired sensors.

[0076] In one specific embodiment, a calibrator, a first absolute pressure sensor, a first temperature sensor, a second absolute pressure sensor, and a second temperature sensor are placed in a temperature- and pressure-adjustable sealed cavity. The distances between the calibrator, the first absolute pressure sensor, the first temperature sensor, the second absolute pressure sensor, and the second temperature sensor within the sealed cavity are within a set threshold range to eliminate differences in environmental pressure caused by positional differences. Then, multiple different temperatures and pressures are set within the sealed container, and the absolute pressure and temperature values ​​measured by the calibrator, the first absolute pressure sensor, the first temperature sensor, the second absolute pressure sensor, and the second temperature sensor within the sealed cavity are obtained and stored to obtain calibration data. This calibration data indicates the correspondence between the absolute pressure and temperature values ​​measured by the calibrator, the first absolute pressure sensor, the first temperature sensor, the second absolute pressure sensor, and the second temperature sensor at different temperatures. Therefore, when the pressure sensor obtains an absolute pressure value, the calibrated pressure range can be obtained through the calibration data; similarly, when the temperature sensor obtains a temperature value, the calibrated temperature range can be obtained through the calibration data.

[0077] Those skilled in the art will know that the calibration data can also be obtained using other calibration methods in the field of measurement.

[0078] See Figure 4 This invention illustrates an exemplary calibration device. A first measuring device 102 and a second measuring device 103 are placed inside a calibration device container 201. The distance between the two is within a set threshold range. A calibration control system 202 controls the ambient temperature and pressure of the calibration device container 201 and ensures that the temperature and pressure inside the calibration device container 201 are sufficiently stable and constant for a sufficiently long time, so that the pressure and temperature deviation measured by the absolute pressure sensor and temperature sensor on the first measuring device 102 and the second measuring device 103 to be implanted is less than the resolution of the sensors.

[0079] The calibration device container 201 contains a high-precision pressure and temperature measuring device, called a calibrator, which is used to provide pressure and temperature values ​​at calibration points. The data receiving and processing unit 203 is used to control the first measuring device 102 and the second measuring device 103 to synchronously measure temperature and pressure, receive and process the temperature and pressure values ​​of the calibrator, the first measuring device 102 and the second measuring device 103, and obtain the calibration data of the first sensor and the second sensor accordingly for subsequent actual measurements.

[0080] Furthermore, the first absolute pressure sensor 310 and the first temperature sensor 309 can be configured as a paired sensor pair, and the second absolute pressure sensor 410 and the second temperature sensor 409 can be configured as another paired sensor pair. Each paired sensor pair is managed using a unique identification code. Calibration of the two absolute pressure sensors must be performed simultaneously within a temperature and pressure calibration system, under the same temperature and pressure conditions.

[0081] Paired absolute pressure sensors should be placed within a set threshold range within the temperature and pressure calibration system. Furthermore, they should be placed close enough to avoid temperature and pressure differences during actual operation exceeding their resolution due to varying locations. Paired absolute pressure sensors can be used in pairs, one for implantation within the biological cavity and the other for measurement in the external environment. Alternatively, multiple external pressure and temperature sensors (e.g., a third absolute pressure sensor and a third temperature sensor) can be calibrated simultaneously for replacement in case the second absolute pressure or temperature sensor fails. During calibration, the paired absolute pressure sensors simultaneously record the temperature and pressure of the standard, as well as the output temperature and pressure measurements of the absolute pressure sensors. The calibrated temperature and pressure ranges need to cover the ambient temperature and pressure ranges for use in the implanted biological body, for example, temperature range: -20 to 60 degrees Celsius; pressure range: 60-101 kPa.

[0082] In one specific embodiment, calibration data as shown in Table 1 is illustrated. This calibration data can be stored in a first measuring device 102 to be implanted, or in a second measuring device 103 in an in vitro measuring environment.

[0083] Table 1: Calibration Data

[0084]

[0085] As shown in Table 1, calibration data is applied to implanted sensors and multiple sets of external environmental sensors. The implanted sensors can be used as the first sensors, including a first absolute pressure sensor and a first temperature sensor, whose temperature and pressure outputs are represented by ti_xx and pi_xx, respectively. Multiple sets of external sensors can be used as the second sensors, including an nth absolute pressure sensor and an nth temperature sensor, whose temperature and pressure outputs are represented by te_xx_n and pex_n, respectively. Uppercase Txx and Px are used to represent the temperature and pressure in the calibrator at the calibration time. Within the pressure range, each pressure point Px requires full temperature range calibration, from Tx to Txn; or for each temperature point, measurements are taken covering all pressure points within the pressure range. The consideration of pairing multiple sensor sets for external use with sensor sets for implantation is based on the harsh external environment, which is prone to contamination or damage, necessitating replacement.

[0086] The pressure monitoring system, using the received first absolute pressure value pi and first temperature value ti, and its own measured second absolute pressure value (i.e., atmospheric pressure value) pe and second temperature value te, combined with stored calibration data, obtains the relative pressure value within the body cavity of the biological organism as follows:

[0087] Using the first temperature value *ti* and the second temperature value *pe*, combined with the corresponding temperature ranges in the stored calibration data, including the temperature ranges of the first temperature sensor, the second temperature sensor, and the calibrator, the calibrated first calibration temperature is obtained through linear interpolation. Second calibration temperature

[0088] Using the first absolute pressure value pi and the second absolute pressure value pe, combined with the corresponding pressure ranges in the stored calibration data, including the pressure ranges of the first temperature sensor, the second temperature sensor, and the calibrator, the temperature range of the calibrator, and the first calibration temperature, the data is analyzed. Second calibration temperature The first calibration absolute pressure after calibration is obtained by linear interpolation. Second calibration absolute pressure

[0089] Calculate the first calibration absolute pressure Second calibration absolute pressure The difference is used to obtain the relative pressure difference Δp.

[0090] This utility model, through a specific example, obtains the relative pressure difference Δp using the following formulas (1)-(5), specifically including:

[0091] The implanted first measuring device 102 obtains the first absolute pressure value pi and the first temperature value ti in the biological body, and sends the measured values ​​back to the second measuring device 103;

[0092] The second measuring device 103 outside the organism obtains the second absolute pressure value pe and the second temperature value te of the environment in which the organism is located.

[0093] Based on ti and pi, te and pe, the temperature range and pressure range of the measuring device are retrieved from the calibration data, such as Table 1. For example, the absolute pressure range and temperature range of the implanted first measuring device 102 are: ti1≤ti≤ti2, pi1≤pi≤pi2, and the standard temperature range and pressure range of the corresponding calibrator are [TI1,TI2] and [PI1,PI2], respectively; the absolute pressure range and temperature range of the second absolute pressure sensor and the second temperature sensor of the second measuring device 103 are te1≤te≤te2, pe1≤pe≤pe2, and the standard temperature range and pressure range of the corresponding calibrator are [TE1,TE2] and [PE1,PE2], respectively.

[0094] The first calibration temperature after calibration was calculated using formulas (1) and (2) respectively. Second calibration temperature

[0095]

[0096] For example, the corresponding calibration data for the measurement data ti = 37.4℃ and pi = 103.236kPa of the implanted measurement device 102 are shown in Table 2.

[0097] Table 2

[0098]

[0099] Then it can be calculated using formula (1):

[0100] For example, the measurement data of the second temperature sensor is te = 17.3℃, and the measurement data of the second absolute pressure sensor is pe = 99.376kPa. The corresponding calibration data are shown in Table 3.

[0101] Table 3

[0102]

[0103] Then, it can be calculated using formula (2):

[0104] Using formulas (3) and (4), the pressure range of the stored calibration data is combined with the first absolute pressure value pi and the second absolute pressure value pe, as well as the first calibration temperature. Second calibration temperature The first calibration absolute pressure after calibration is obtained by linear interpolation. Second calibration absolute pressure

[0105] Specifically, the first calibration absolute pressure of the first measuring device 102 Calculated using formula (3),

[0106]

[0107] Using the calibration data in Table 2 above, the following can be calculated according to formula (3):

[0108]

[0109] The second calibration absolute pressure of the second measuring device 103 Calculated using formula (4),

[0110]

[0111] Calculate the first calibration absolute pressure using formula (5) Second calibration absolute pressure The difference is used to obtain the relative pressure Δp.

[0112]

[0113] Using the calibration data in Table 3 above, the following can be calculated according to formula (4):

[0114]

[0115] Finally, the pressure Δp in the measuring cavity is obtained according to formula (5).

[0116] Δp=2.345KPa

[0117] Therefore, this utility model employs a small-range linear interpolation method. Based on the first absolute pressure value pi and the first temperature value ti output by the implanted first measuring device 102, and the second absolute pressure value (i.e., atmospheric pressure value) pe and the second temperature value te measured by itself, combined with the stored calibration data, the relative pressure value inside the biological cavity is obtained. Formulas (1)-(5) and the corresponding calibration data are stored in the memory of the second measuring device 103 and calculated by the second measuring device 103 through the corresponding algorithm.

[0118] However, this invention is not limited thereto. The first measuring device 102 can also store corresponding calibration data and calculate the first calibration temperature using a formula. and the first calibration absolute pressure Then the first calibration temperature and the first calibration absolute pressure The data is sent to the second measuring device 103, which calculates the second calibration temperature. Second calibration absolute pressure And the calculation of the subsequent relative pressure difference. That is, the above calculation process can be calculated by the control unit of the first measuring device 102 and the second measuring device 103, or by other external control units, based on the above measurement data and calibration data. All the above transformations are within the protection scope of this utility model.

[0119] An exemplary temperature-pressure calibration method is also shown, but this invention is not limited thereto. For measuring devices integrating temperature and pressure sensors, the manufacturer's corresponding temperature-pressure calibration method can also be used to obtain the pressure of the object being measured. Furthermore, multiple pressure sensors need to be calibrated under the same temperature and pressure environment to avoid systematic measurement errors. Additionally, nonlinear interpolation can be used for calibration and measurement data calibration. The calibration of the aforementioned measuring devices in the prior art, as well as the correction and calculation of measurement data using calibration data, are all within the scope of protection of this invention.

[0120] Furthermore, once the sensors (including absolute pressure and temperature sensors) of the first measuring device 102 implanted in the biological cavity and another set of sensors (including absolute pressure and temperature sensors) of the second measuring device 103 outside the biological cavity are successfully paired after calibration in the same sealed cavity, during measurement, without interrupting wireless power and signal transmission, pairing is not required before each measurement, and pressure sequences for monitoring can be continuously collected and calculated.

[0121] To ensure measurement accuracy, the spatial distance between the first measuring device 102 and the second measuring device 103 of this invention, especially the first absolute pressure sensor and the second absolute pressure sensor, needs to be sufficiently close, and the distance should be less than the threshold range mentioned above.

[0122] The implanted first measuring device 102 obtains low-power electrical energy through electromagnetic coupling with the external second measuring device 103. The power required for the operation of the sensor and circuit is obtained through the circuit of the implanted first measuring device 102, and the digital measurement results of the sensor in the first measuring device are transmitted back through load modulation of the coupled electromagnetic field.

[0123] Therefore, this utility model uses the first measuring device 102 and the second measuring device 103 to obtain temperature-independent and calibrated pressure values ​​inside and outside the biological cavity through the first and second absolute pressure sensors inside and outside the biological cavity, and calculates the pressure difference. Thus, the pressure difference inside the biological cavity can be continuously obtained without the need for fistula creation. It has the advantages of long time and continuous operation. Its continuous working capability depends only on the continuous working capability of the second measuring device 103 outside the body.

[0124] See Figure 2 The diagram shows a structural block diagram of a first measuring device 102 implanted in the body cavity of a biological body according to a specific embodiment of the present invention. The first measuring device 102 includes a first coil antenna 301, a first power supply 302, a first controller 303, a first absolute pressure sensor 310, and a first temperature sensor 309.

[0125] The first coil antenna 301 is used for wireless signal transmission and wireless charging. The wireless signal transmission includes receiving control signals and data signals. The data signals may include pressure values ​​and temperature values. For example, they may be measured pressure values ​​and temperature values ​​or calibrated pressure values ​​and temperature values.

[0126] The first power supply 302 is used to condition the received power signal into the power signal required for the operation of the first controller 303, the first absolute pressure sensor 310, and the first temperature sensor 309.

[0127] The first controller 303 is used to receive the control signal from the second measuring device 103 and control the first absolute pressure sensor 310 and the first temperature sensor 309 to perform data acquisition, calculation and transmission.

[0128] The first absolute pressure sensor 310, used to measure the pressure value within the cranial cavity, includes a first absolute pressure sealed cavity 305, a first open cavity 306, and a first pressure-sensitive element 308 located between the two. The first pressure-sensitive element 308 is located away from the pressure range of the object being measured in the first absolute pressure sealed cavity 305. The open cavity 306 faces the area where the pressure needs to be measured. The first pressure-sensitive element 308 is used to convert the pressure difference between the absolute pressure cavity and the open cavity into an electrical signal suitable for measurement.

[0129] The first temperature sensor 309 is used to measure the first temperature;

[0130] The first conditioning and analog-to-digital conversion circuit 304 is used to power the first pressure-sensitive element 308 and the first temperature sensor 309, and to obtain the measured pressure and temperature signals and transmit them to the first controller 303.

[0131] Furthermore, the first controller 303 also has a storage function for storing one or more of the following: unique identification codes of the first absolute pressure sensor and the first temperature sensor, calibration parameters of pressure and temperature, unique identification codes and calibration parameters of other paired pressure and temperature sensors.

[0132] Depending on the pressure area being measured, the first pressure-sensitive element 308 also includes a pressure-conducting tube 307, which is connected to the first open cavity 306 for measuring pressure, and is used for pressure measurement in areas such as the ventricles. However, the pressure-conducting tube 307 is not mandatory; it may not be necessary for superficial epidural or subdural pressure measurements. The pressure-conducting tube 307 is typically a thin silicone tube.

[0133] The first temperature sensor 309 can be integrated with the first absolute pressure sensor 310 or set separately. The illustration is only used to represent two corresponding functional modules and is not an example of their positions.

[0134] See Figure 3 The diagram shows a schematic of a second measuring device 103 located on the outside of an organism according to a specific embodiment of the present invention; the second measuring device 103 includes a second coil antenna 401, a second power supply 402, a second controller 403, a wireless transceiver unit 412, a communication unit 414, a second absolute pressure sensor 410, and a second temperature sensor 409.

[0135] The second coil antenna 401 is used for wireless signal transmission and wireless charging. The wireless signal transmission includes sending control signals and receiving data signals. The data signals may include pressure and temperature values, which, for example, may be pressure and temperature values ​​measured by the first measuring device 102 or calibrated pressure and temperature values. Wireless charging utilizes electromagnetic coupling to charge the first coil antenna 301.

[0136] The second power source 402 is used to power the device of the second measuring device. In an optional embodiment, the second power source 402 can be connected to a local power source 415 (e.g., a common battery or a rechargeable battery) to obtain power from the local source, or to charge the local power source 415 through an external power supply unit 416, or to directly power the second power source 402.

[0137] The second controller 403 is used to control the various components of the second measuring device 103 and send control signals to the first measuring device 102;

[0138] The wireless transceiver unit 412 is connected to the second coil antenna 401 via a cable 411 and is used for transmitting and receiving electrical energy, control signals and measurement data. For example, it can be fabricated on the circuit board of the second measuring device 103.

[0139] The second absolute pressure sensor 410 is used to measure the environmental pressure of an organism. As mentioned above, the second absolute pressure sensor 410 has the same specifications as the first absolute pressure sensor 310, specifically including a second absolute pressure sealed cavity 405, a second open cavity 406, and a second pressure sensitive element 408 located between the two. The second absolute pressure sealed cavity 405 is located away from the pressure range of the object being measured, while the second pressure sensitive element 408 is located away from the pressure range of the object being measured. The open cavity 406 faces the area where the pressure needs to be measured. The second pressure sensitive element 408 is used to convert the pressure difference between the absolute pressure cavity and the open cavity into an electrical signal suitable for measurement. The pressure guide hole 407 is used to connect atmospheric pressure to the second open cavity 406. It usually has an open pressure cavity protection device to prevent the sensor pressure guide hole from being blocked or the sensitive element from being contaminated.

[0140] The second temperature sensor 409 is used to measure the second temperature of the biological environment. As mentioned above, the second temperature sensor 409 has the same specifications as the first temperature sensor 410.

[0141] The second conditioning and analog-to-digital conversion circuit 404 is used to power the second pressure-sensitive element 408 and the second temperature sensor 409, and to obtain the measured pressure and temperature signals and transmit them to the second controller 403.

[0142] The communication unit 414 is used to connect to the relay device 413 via wired or wireless communication, so that the user can easily obtain the corresponding temperature and pressure data, as well as the calculated relative pressure value.

[0143] Wired methods include, but are not limited to, USB, CAN, Ethernet, fiber optic, or RS232 transmission methods.

[0144] Wireless methods include, but are not limited to, Bluetooth, WiFi, and other wireless communication methods. For example, existing low-frequency and high-frequency technologies that do not require wireless licenses, such as the Industrial-Scientific-Military (ISM) band, may use 125kHz or 134kHz frequencies for low frequencies and 13.56MHz frequencies for high frequencies, depending on the country and region. The power consumption of wireless power transmission is controlled in the μW level to avoid discomfort to the host due to excessive power consumption and heat generated by the implanted sensor.

[0145] In this invention, the second controller 403 can store the above formulas (1)-(5), pressure and temperature calibration parameters, thereby calibrating the pressure and temperature inside the cavity and the environment, as well as calculating the relative pressure.

[0146] Therefore, this utility model has the following advantages:

[0147] 1. A first measuring device and a second measuring device are respectively set on the inside and outside of the organism. Only one surgery is needed to implant the first measuring device into the cavity, eliminating the need for fistula creation, overcoming the problem of difficult hygiene maintenance, eliminating the need for the organism to be in a specific environment, and allowing the organism to move freely.

[0148] 2. The first measuring device can be wirelessly powered by the wireless coil of the second measuring device, extending the power supply time and expanding the power supply mode, so that the first measuring device can continuously measure the internal pressure and perform long-term continuous monitoring.

[0149] 3. By using absolute pressure and temperature sensors and calibration data to calibrate temperature and pressure, temperature-independent calibrated intracavitary pressure values ​​and pressure differences are obtained, thereby improving overall measurement accuracy and obtaining high-precision intracavitary pressure values.

[0150] 4. Pressure and temperature sensors can be managed and paired using unique codes, improving calibration accuracy.

[0151] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A system for monitoring pressure in a biological lumen, comprising: include: A first measuring device implanted in the cavity of a biological organism and a second measuring device outside the biological organism. The first measuring device includes a first absolute pressure sensor, a first temperature sensor, and a first coil antenna. The first absolute pressure sensor is used to measure the first absolute pressure value pi of the biological cavity; the first temperature sensor is used to measure the first temperature value ti of the biological cavity; and the first coil antenna is used to receive control signals, measure pressure and temperature, and transmit the measured pressure and temperature values. The second measuring device includes a second absolute pressure sensor, a second temperature sensor, and a second coil antenna. The second absolute pressure sensor is used to measure the second absolute pressure value pe of the environment in which the organism is located; the second temperature sensor is used to measure the second temperature value te of the environment in which the organism is located; and the second coil antenna is used to electromagnetically couple with the first coil antenna to send control signals, so that the first measuring device performs temperature and pressure measurements and sends the measured pressure and temperature values. The distance between the first absolute pressure sensor and the second absolute pressure sensor is within a set threshold range; The monitoring system uses the first absolute pressure value pi and the first temperature value ti inside the biological cavity, and the second absolute pressure value pe and the second temperature value te of the biological environment, combined with the stored calibration data, to obtain the relative pressure value inside the biological cavity.

2. The pressure monitoring system according to claim 1, characterized in that: The threshold range is less than the atmospheric elevation difference corresponding to the lowest pressure resolution of the first and second absolute pressure sensors.

3. The pressure monitoring system according to claim 2, characterized in that: The first absolute pressure sensor and the first temperature sensor form a pair of paired sensors, and the second absolute pressure sensor and the second temperature sensor form another pair of paired sensors.

4. The pressure monitoring system according to claim 2 or 3, characterized in that: The second measuring device controls the electromagnetic coupling between the first coil antenna and the second coil antenna to supply power to the first measuring device.

5. The pressure monitoring system according to claim 4, characterized in that: The first measuring device includes a first coil antenna, a first power supply, a first controller, a first absolute pressure sensor, and a first temperature sensor; The first coil antenna is used for wireless signal transmission and wireless charging. The first power supply is used to condition the received power signal into the power signal required for the operation of the first controller, the first absolute pressure sensor, and the first temperature sensor. The first controller is used to receive control signals from the second measuring device and control the first absolute pressure sensor and the first temperature sensor to perform data acquisition, calculation and transmission. The first temperature sensor is used to measure the first temperature.

6. The pressure monitoring system according to claim 5, characterized in that: The first absolute pressure sensor includes: a first absolute pressure sealed cavity, a first open cavity, and a first pressure-sensitive element located between the two. The first pressure-sensitive element is located in the pressure range of the first absolute pressure sealed cavity away from the object being measured. The first open cavity faces the area where the pressure needs to be measured. The first pressure-sensitive element is used to convert the pressure difference between the absolute pressure cavity and the open cavity into an electrical signal suitable for measurement.

7. The pressure monitoring system according to claim 6, characterized in that: The first absolute pressure sensor further includes a first conditioning and analog-to-digital conversion circuit for powering the first pressure-sensitive element and the first temperature sensor, and for obtaining the measured pressure and temperature signals and transmitting them to the first controller.

8. The pressure monitoring system according to claim 4, characterized in that: The second measuring device includes a second coil antenna, a second power supply, a second controller, a wireless transceiver unit, a communication unit, a second absolute pressure sensor, and a second temperature sensor. The second coil antenna is used for wireless signal transmission and wireless charging. The second power source is used to power the equipment of the second measuring device; The second controller is used to control the various components of the second measuring device and send control signals to the first measuring device. The wireless transceiver unit is connected to the second coil antenna via a cable and is used for transmitting and receiving electrical power, control signals, and measurement data. The second temperature sensor is used to measure the second temperature of the organism's environment.

9. The pressure monitoring system according to claim 8, characterized in that: The second absolute pressure sensor includes: a second absolute pressure sealed cavity, a second open cavity, and a second pressure-sensitive element located between the two. The second pressure-sensitive element is located in the pressure range of the second absolute pressure sealed cavity away from the object being measured. The second open cavity faces the area where the pressure needs to be measured. The second pressure-sensitive element is used to convert the pressure difference between the absolute pressure cavity and the open cavity into an electrical signal suitable for measurement. A pressure guide hole is used to connect atmospheric pressure to the second open cavity.

10. The pressure monitoring system according to claim 9, characterized in that: The second absolute pressure sensor also includes a second conditioning and analog-to-digital conversion circuit for powering the second pressure-sensitive element and the second temperature sensor, and for obtaining the measured pressure and temperature signals and transmitting them to the second controller; It also includes a communication unit for connecting to a relay device via wired or wireless communication, so that users can easily obtain the corresponding temperature and pressure data, as well as the calculated relative pressure value.

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