JP6890845B2 - Pressure ulcer detection device and pressure ulcer detection method - Google Patents

Description

Embodiments of the present invention relate to a pressure ulcer detection device and a pressure ulcer detection method.

Pressure ulcers are local skin and subcutaneous tissue damage caused by prolonged pressure on the skin and reduced blood flow. Pressure ulcers are classified by the US Pressure Ulcer Advisory Board (NPUAP: National Pressure Ulcer Advisory Panel), the European Pressure Ulcer Advisory Board (EPUAP: European Pressure Ulcer Advisory Panel), and the pressure ulcers are classified from stage I to stage IV. ing. Pressure ulcers can be treated early to shorten their treatment period.

For pressure ulcer detection systems, a technology that detects pressure ulcers by measuring spatially correlated complex impedances in vivo, consisting of a multi-electrode array that contacts the skin and control hardware that performs impedance spectroscopy. It is known (see, for example, Non-Patent Document 1).
Further, regarding a system for detecting a pressure ulcer, a technique for detecting a pressure ulcer by irradiating a wearable sensor composed of a flexible laminate and a copper wire and irradiating a microwave to detect damage to a deep tissue is known. (See, for example, Non-Patent Document 2).

Sarah L. Swisher, Monica C. Lin, Amy Liao, Elisabeth J. Leeflang, Yasser Khan, Felippe J. Pavinatto, Kaylee Mann, Agne Naujokas, David Young, Shuvo Roy, Michael R. Harrison, Ana Claudia Arias, Vivek Subramanian & Michel M. Maharbiz, “Impedance sensing device enables early detection of pressure ulcers in vivo”, nature COMMUNICATIONS, 6:6575, 2015 Hamid Moghadas, Vivian K. Mushahwar, “Passive microwave actuator sensor for detection of deep tissue injuries”, Sensors & Actuators: B. Chemical vol.277 (2018) 69-77

However, in the technique described above, the sensor is attached directly to the skin. For example, the sensor includes gold-plated electrodes and copper wire. Since the sensor is attached directly to the skin, it is necessary to replace the antenna regularly for hygiene reasons. In addition, when the sensor is directly attached to the skin for a long period of time, it may induce skin diseases such as swelling. Also, this technique cannot be used for patients with metal allergies.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a pressure ulcer detection device capable of detecting a pressure ulcer and a pressure ulcer detection method.

One embodiment of the present invention is based on an antenna that transmits a microwave to a living body and receives the transmitted reflected wave of the microwave, a feeding unit that feeds the antenna, and the reflected wave received by the antenna. Based on the detection unit that detects decubitus and the reflection coefficient derived by deriving the reflection coefficient based on the reflected wave detected by the detection unit, and the reflected wave obtained when the microwave is transmitted to a healthy living body. The antenna is provided with a derivation unit for deriving the degree of decubitus based on the reflection coefficient derived from the above and an output unit for outputting information indicating the degree of decubitus derived by the derivation unit. a pressure sore detector that will be installed in contact.
In one embodiment of the present invention, in the pressure ulcer detection device described above, the antenna is a patch antenna containing conductive fibers.
In one embodiment of the present invention, the pressure ulcer detection device includes an antenna processing unit that switches the frequency of microwaves transmitted by the antenna, and the antenna is based on the frequency switched by the antenna processing unit. Sends microwaves to the living body.
In one embodiment of the present invention, in the pressure ulcer detection device described above, the antenna includes a plurality of antennas, the feeding unit feeds each of the plurality of antennas, and each of the antennas makes a microwave to a living body. The detection unit detects the pressure ulcer based on the reflected wave of the microwave transmitted by each of the plurality of antennas, and the output unit detects the detection result of the pressure ulcer detected by the detection unit. Output.

One embodiment of the present invention is based on a step of feeding an antenna, a step of transmitting a microwave to a living body, a step of receiving a reflected wave of the transmitted microwave, and a step of receiving the reflected wave of the antenna. , The step of detecting decubitus, the reflectance coefficient derived by deriving the reflectance coefficient based on the reflected wave, and the reflectance coefficient derived based on the reflected wave obtained when the microwave is transmitted to a healthy living body. based on the steps of deriving the degree of pressure ulcer, possess and outputting information indicating the degree of pressure ulcers derived in the step of deriving, said antenna, Ru is installed in the living body and non-contact, pressure sores It is a decubitus detection method performed by a detector.

According to the embodiment of the present invention, it is possible to provide a pressure ulcer detection device capable of detecting a pressure ulcer and a pressure ulcer detection method.

It is a figure which shows an example of the pressure ulcer detection apparatus which concerns on embodiment. It is a block diagram which shows an example of the pressure ulcer detection apparatus which concerns on embodiment. It is a figure which shows an example of the reflectance coefficient information. It is a figure which shows an example of a living tissue. It is a figure which shows an example of the modeling of a living tissue. It is a figure which shows an example of the result of the simulation which obtains the reflection coefficient. It is a flowchart which shows an example of the operation of the pressure ulcer detection apparatus which concerns on this embodiment. It is a block diagram which shows an example of the pressure ulcer detection apparatus which concerns on modification 1 of embodiment. It is a figure which shows an example of the relationship between a pressure ulcer stage and a reflectance coefficient. It is a flowchart which shows an example of the operation of the pressure ulcer detection apparatus which concerns on modification 1 of embodiment. It is a block diagram which shows an example of the pressure ulcer detection apparatus which concerns on modification 2 of embodiment. It is a figure which shows an example of the reflectance coefficient information. It is a flowchart which shows an example of the operation of the pressure ulcer detection apparatus which concerns on modification 2 of embodiment.

Next, the pressure ulcer detection device and the pressure ulcer detection method according to the embodiment of the present invention will be described with reference to the drawings. The embodiments described below are merely examples, and the embodiments to which the present invention is applied are not limited to the following embodiments.
In all the drawings for explaining the embodiment, the same reference numerals are used for those having the same function, and the repeated description will be omitted.
Further, "based on XX" in the present application means "based on at least XX", and includes a case where it is based on another element in addition to XX. Further, "based on XX" is not limited to the case where XX is directly used, but also includes the case where it is based on the case where calculation or processing is performed on XX. "XX" is an arbitrary element (for example, arbitrary information).

(Embodiment)
(Decubitus ulcer detection device)
Hereinafter, the pressure ulcer detection device according to the embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing an example of a pressure ulcer detection device according to an embodiment.
The pressure ulcer detection device 100 according to the embodiment detects the pressure ulcer when the pressure ulcer is generated in a part of a living body such as a patient. Hereinafter, the case where the patient PA is applied as an example of a living body will be described.

The pressure ulcer detection device 100 includes an antenna 102 and a control device 110. The antenna 102 and the control device 110 are connected by a feeder line 104. Further, FIG. 1 shows a patient PA lying on a mattress 20 placed on a bed 30 with his head placed on a pillow 10. The antenna 102 is installed between the bed 30 and the mattress 20 resting on the bed 30.

A person who intends to detect a pressure ulcer using the pressure ulcer detection device 100 (hereinafter referred to as “user”) installs an antenna 102 under the site where the pressure ulcer is detected in the patient PA, and causes the pressure ulcer to the control device 110. Perform an operation to detect. By this operation, high frequency power is supplied from the control device 110 to the antenna 102 via the feeding line 104. FIG. 1 shows a case where the sacral region is used as an example of a site for detecting a pressure ulcer.
The antenna 102 transmits microwaves by the high frequency power supplied by the control device 110. The microwave transmitted from the antenna 102 is applied to the site where the pressure ulcer is detected in the patient PA. The microwave is applied to the site where the pressure ulcer is detected, and the irradiated microwave is reflected by the pressure ulcer to generate a reflected wave. The reflected wave is received by being captured by the antenna 102. The high-frequency power generated by the antenna 102 capturing the reflected wave is supplied from the antenna 102 to the control device 110.
The control device 110 detects pressure ulcers based on the high frequency power supplied by the antenna 102. The control device 110 outputs a pressure ulcer detection result.
Hereinafter, the antenna 102 included in the pressure ulcer detection device 100 and the control device 110 will be sequentially described.

FIG. 2 is a block diagram showing an example of the pressure ulcer detection device of the embodiment.
The antenna 102 will be described. An example of the antenna 102 is a planar antenna such as a patch antenna. The operating frequency of the antenna 102 is in the 1 GHz to 10 GHz band. Further, the operating frequency of the antenna 102 may be in the 24 GHz band. An example of the antenna 102 includes a dielectric substrate 107, a radiating element 106 formed on both sides of the dielectric substrate 107, and a ground conductor plate 108 as constituent elements. When the radiating element 106 and the ground conductor plate 108 are formed on the dielectric substrate 107, they may be formed by printing, or may be formed by pasting a metal foil or a conductive cloth. The radiating element 106 has a structure equivalent to that of a microstrip line having a length of La and a width of W and both ends are open, and La resonates at a frequency corresponding to an integral multiple of a 1/4 wavelength. Further, the antenna 102 has a feeding unit 109 that supplies power to the antenna 102. The antenna 102 is installed so that the radiating element 106 sandwiches the mattress 20 and faces the site where the pressure ulcer of the patient PA is detected. When the control device 110 outputs high-frequency power, the antenna 102 transmits microwaves by the output high-frequency power.

The control device 110 will be described. The control device 110 is realized by a device such as a personal computer, a server, a smartphone, a tablet computer, or an industrial computer.
In the control device 110, for example, the antenna processing unit 115, the storage unit 120, the information processing unit 130, the display unit 140, the operation unit 160, the power supply unit 170, and each component are shown in FIG. It is provided with a bus line 150 such as an address bus and a data bus for electrically connecting as described above.
The antenna processing unit 115 is realized by including a power feeding module and a network analyzer. The antenna processing unit 115 acquires information indicating that power is supplied to the power feeding unit 109 output by the information processing unit 130. The antenna processing unit 115 uses the power supply unit 170 to supply high-frequency power to the power supply unit 109 via the feeder line 104 based on the acquired information indicating that the power supply unit 109 is supplied with power. The antenna processing unit 115 acquires the high-frequency power output by the antenna 102, down-converts the acquired high-frequency power, and digitizes the down-converted high-frequency power. The antenna processing unit 115 outputs the result of digitizing the down-converted high-frequency power to the information processing unit 130.

The storage unit 120 is realized by, for example, a RAM, a ROM, an HDD, a flash memory, or a hybrid storage device in which a plurality of these are combined. Instead of providing a part or all of the storage unit 120 as a part of the control device 110, an external device such as NAS or an external storage server that can be accessed by the processor of the control device 110 via a network (not shown). It may be realized by the device. The storage unit 120 stores the program 121 executed by the information processing unit 130 and the application 122. Further, the reflection coefficient information 123 is stored in the storage unit 120.

Program 121, for example, is an operating system that sits between the user or application program and the hardware, providing a standard interface to the user or application program while at the same time being efficient for each resource such as the hardware. Management.
The application 122 includes a module that causes the control device 110 to transmit microwaves to the antenna 102 by supplying high-frequency power to the feeding unit 109 of the antenna 102. The application 122 includes a module for causing the control device 110 to receive the reflected wave of the microwave transmitted to the antenna 102. The app 122 includes a module that causes the control device 110 to detect a pressure ulcer based on the received reflected wave. The application 122 includes a module that causes the control device 110 to output a pressure ulcer detection result.
Reflection coefficient information 123 will be described.
FIG. 3 is a diagram showing an example of reflectance coefficient information. The reflectance coefficient information 123 is based on the date and time when the pressure ulcer detection device 100 performs the process of detecting the pressure ulcer for each patient identification information and the reflected wave of the microwave transmitted to the site where the pressure ulcer is detected on that date and time. It is the information in the table format that is associated with the result of deriving. In the example shown in FIG. 3, the date and time "***** year *** month ** day" and the reflectance coefficient "***" are associated with each other for the patient identification information "AAA001", and the date and time "++++ year ++ month". "++ day" is associated with the reflection coefficient "++++", and the date and time "#### year ## month ## day" is associated with the reflection coefficient "***". It is preferable that the reflectance coefficient information 123 stores the association between the date and time and the reflectance coefficient even before the pressure ulcer is detected. The explanation will be continued by returning to FIG.

The operation unit 160 includes an input device and accepts user operations. This input device includes a device for inputting character information such as a keyboard, a pointing device such as a mouse and a touch panel, a button, a dial, a joystick, a touch sensor, a touch pad, and the like.
The display unit 140 is controlled by a processor such as a CPU to display an image, a GUI (Graphical User Interface), or the like. In this example, the operation unit 160 is a touch panel.
The power supply unit 170 supplies power to each unit of the control device 110.

The information processing unit 130 is a software function unit realized by, for example, a processor such as a CPU executing a program 121 stored in the storage unit 120 and an application 122. All or part of the information processing unit 130 may be realized by hardware such as LSI, ASIC, or FPGA, or may be realized by a combination of software function unit and hardware.
The information processing unit 130 functions as, for example, a reception unit 131, a processing unit 132, a detection unit 133, and an output unit 134.
The reception unit 131 receives information indicating that the pressure ulcer output by the operation unit 160 is detected by the user performing an operation for detecting the pressure ulcer on the operation unit 160. The reception unit 131 outputs information indicating that the received pressure ulcer is detected to the processing unit 132. Specifically, the user inputs the identification information of the patient PA and performs an operation of detecting the pressure ulcer. By this operation, the operation unit 160 outputs the information indicating that the pressure ulcer including the identification information of the patient PA is detected to the reception unit 131.

The processing unit 132 acquires information indicating that the pressure ulcer is detected, which is output by the reception unit 131, and supplies power to the antenna processing unit 115 to the power feeding unit 109 based on the information indicating that the acquired pressure ulcer is detected. Outputs information indicating. The processing unit 132 acquires the patient PA identification information from the information indicating that the pressure ulcer is detected, and outputs the acquired patient PA identification information to the detection unit 133.
The detection unit 133 acquires the patient PA identification information output by the processing unit 132. The detection unit 133 acquires the result of digitizing the down-converted high-frequency power output by the antenna processing unit 115, and detects the pressure ulcer based on the result of digitizing the acquired down-converted high-frequency power. Specifically, the detection unit 133 derives the reflection coefficient based on the result of digitizing the down-converted high-frequency power. The detection unit 133 acquires a table corresponding to the identification information of the patient PA from the reflection coefficient information 123, and stores the date and time when the reflection coefficient is derived and the derived reflection coefficient in association with each other in the acquired table. It is assumed that the detection unit 133 has detected a pressure ulcer when the derived reflection coefficient is equal to or more than the reflection coefficient threshold value, and has not detected a pressure ulcer when the reflected reflection coefficient is less than the reflection coefficient threshold value. The detection unit 133 outputs information indicating whether or not a pressure ulcer has been detected to the output unit 134.
The output unit 134 acquires information indicating whether or not the pressure ulcer output by the detection unit 133 has been detected, and processes the information indicating whether or not the acquired pressure ulcer has been detected to display the pressure ulcer on the display unit 140. Display whether or not it was detected.

Here, a process for detecting a pressure ulcer will be described. First, the biological tissue will be described.
FIG. 4 is a diagram showing an example of a living tissue. FIG. 4 shows an image of a vertical cross section of the living tissue and each layer constituting the living tissue. In FIG. 4, the upper figure shows an example of a healthy living tissue, and the lower figure shows an example of a living tissue in which a pressure ulcer is generated.
This will be described with reference to the upper figure of FIG. An example of a longitudinal section of normal living tissue is bone 202, muscle layer 204 laminated on bone 202, fat layer 206 laminated on muscle layer 204, and laminated on fat layer 206. Includes skin layer 208 and the like. According to the example of FIG. 4, the thickness of the bone 202 is 17.5 mm, the thickness of the muscle layer 204 is 2.2 mm, the thickness of the fat layer 206 is 4.4 mm, and the thickness of the skin layer 208 is The thickness is 3.5 mm.
This will be described with reference to the lower figure of FIG. An example of a longitudinal section of living tissue in which pressure ulcers occur is a blood layer between the fat layer 206 and the skin layer 208, in addition to the bone 202, the muscle layer 204, the fat layer 206, and the skin layer 208. 210 is formed. The width and position of the blood layer 210 varies with the stage indicating the depth of pressure ulcer damage. Here, stage I is a state in which the skin surface is not damaged. Stage II is a condition in which the damage remains up to the dermis. Stage III is a condition in which the adipose tissue is damaged. Stage IV is a condition in which the injury is accompanied by exposure of bones, tendons, and muscles.

Next, modeling of living tissue will be described. Based on an example of the biological tissue shown in FIG. 4, the biological tissue was modeled. The modeling of the biological tissue was performed based on the thickness of each layer constituting the biological tissue.
FIG. 5 is a diagram showing an example of modeling of a living tissue. In FIG. 5, the left figure shows an example of modeling a healthy living tissue, and the right figure shows an example of modeling a living tissue in which a pressure ulcer occurs. Further, in FIG. 5, the skin layer 208 is indicated by the X-axis and the Y-axis, and the direction orthogonal to the X-axis and the Y-axis is defined as the Z-axis. Further, the direction from the skin layer 208 to the bone 202 is defined as the positive direction of the Z axis.
An example of modeling a healthy living tissue will be described with reference to the left figure of FIG. An example of a healthy biological tissue model is a bone 202m, a muscle layer 204m formed in the negative direction of the Z axis of the bone 202m, a fat layer 206m formed in the negative direction of the Z axis of the muscle layer 204m, and a fat layer. Includes a skin layer 208 m formed in the negative direction of the Z axis of 206 m. Here, the thickness of the bone 202 m is 17.6 mm, the thickness of the muscle layer 204 m is 2.2 mm, the thickness of the fat layer 206 m is 4.40 mm, and the thickness of the skin layer 208 m is 3.4 mm. .. Here, the length is the length in the Z-axis direction.
Further, an air layer 220 m is formed on the minus side of the Z axis of the skin layer 208 m. The thickness of the air layer 220 m was set to 30.0 mm. The antenna 102 is formed at a position facing the skin layer 208 m of a healthy biological tissue model with the air layer 220 m in between. The area of the XY plane of the healthy biological tissue model was 100 mm × 100 mm.

An example of modeling a living tissue in which a pressure ulcer is occurring will be described with reference to the right figure of FIG. An example of a biological tissue model in which pressure ulcers occur is a bone 202 m, a muscle layer 204 m formed in the negative direction of the Z axis of the bone 202 m, and a fat layer 206 m formed in the negative direction of the Z axis of the muscle layer 204 m. In addition to the skin layer 208 m formed in the negative direction of the Z axis of the fat layer 206 m, the blood layer 210 m formed between a part of the muscle layer 204 m and a part of the fat layer 206 m is included. The portion from the blood layer 210 m to the skin layer 208 m in the Z-axis direction has a defect range of 212 m because the properties are often different from those of the skin layer 208 m. Here, the thickness of the bone 202 m is 17.6 mm, the thickness of the muscle layer 204 m is 2.2 mm, the thickness of the fat layer 206 m is 4.40 mm, and the thickness of the skin layer 208 m is 3.4 mm. The thickness of the blood layer 210 m was set to 1.00 mm.
Further, an air layer 220 m is formed on the minus side of the Z axis of the skin layer 208 m. The thickness of the air layer 220 m was set to 30.0 mm. The antenna 102 is formed at a position facing the defect range 212 m of the skin layer 208 m of the biological tissue model in which the pressure ulcer is generated, sandwiching the air layer 220 m. The area of the XY plane of the biological tissue model in which the pressure ulcer is generated was set to 100 mm × 100 mm. The area of the XY plane of the blood layer 210 m was defined as L mm × L mm.

Using a healthy biological tissue model and a biological tissue model in which pressure ulcers are generated, a simulation was performed to obtain the reflectance coefficient when microwaves were irradiated to the biological tissue from the antenna 102. In the healthy biological tissue model and the biological tissue model in which pressure ulcers occur, the parameters of the skin layer 208 m are set to εr = 3.294 and σ = 0.62 S / m, and the parameters of the fat layer 206 m are set to εr =. 4.56, σ = 0.62 S / m, the parameters of the muscle layer 204 m are εr = 42.08, σ = 11.35 S / m, and the parameters of the bone 202 m are εr = 7.96, σ = 2. It was set to .24 S / m, and the parameters of the blood layer 210 m were set to εr = 44.25 and σ = 13.95 S / m. Note that εr is strain and σ is stress. The microwave frequency was 10.5 GHz. The FDTD method (Finite-difference time-domain method) was used for the analysis.

FIG. 6 is a diagram showing an example of the result of the simulation for obtaining the reflection coefficient. In FIG. 6, the horizontal axis is the frequency [GHz] and the vertical axis is the reflection coefficient [dB]. In addition, it was set to L = 10. A simulation was performed to determine the reflectance coefficient of a healthy biological tissue model and a biological tissue model in which pressure ulcers occur. For the biological tissue model in which pressure ulcers are occurring, simulations were performed for those corresponding to each of stage I to stage IV.
According to FIG. 6, it can be seen that the difference between the reflectance coefficient obtained from the healthy biological tissue model and the reflectance coefficient obtained from the biological tissue model in which the pressure ulcer corresponding to stage I is generated is small. However, the reflectance coefficient obtained from a healthy biological tissue model (reflective coefficient obtained from a biological tissue model in which pressure ulcers corresponding to stage I are generated) and pressure ulcers obtained from each of stage II to stage IV occur. It can be seen that there is a difference of 3 dB to 4 dB with the reflectance coefficient obtained from the living tissue model. This is to irradiate the part of the patient PA where the pressure ulcer is detected with microwaves, and detect the pressure ulcer after stage II by the value of the reflectance coefficient derived based on the reflected wave. It shows that it can be done.

(Operation of pressure ulcer detection device)
FIG. 7 is a flowchart showing an example of the operation of the pressure ulcer detection device according to the present embodiment. In FIG. 7, the patient PA lies on the mattress 20 placed on the bed 30 with the head resting on the pillow 10, under the site where the pressure ulcer of the patient PA is detected, and the bed 30 and the mattress. The operation after the user installs the antenna 102 is shown between the 20 and the 20.
(Step S1)
The reception unit 131 receives information indicating that the pressure ulcer output by the operation unit 160 is detected by the user inputting the identification information of the patient PA to the operation unit 160 and performing an operation for detecting the pressure ulcer. The reception unit 131 outputs information indicating that the received pressure ulcer is detected to the processing unit 132.
The processing unit 132 acquires information indicating that the pressure ulcer is detected, which is output by the reception unit 131, and supplies power to the antenna processing unit 115 to the power feeding unit 109 based on the information indicating that the acquired pressure ulcer is detected. Outputs information indicating. In addition, the processing unit 132 acquires the identification information of the patient PA from the information indicating that the pressure ulcer is detected, and outputs the information indicating the acquired patient PA to the detection unit 133.
The antenna processing unit 115 acquires information indicating that power is supplied to the power supply unit 109 output by the information processing unit 130, and outputs high-frequency power to the antenna 102 based on the information indicating that power is supplied to the acquired power supply unit 109. To do. When the control device 110 outputs high-frequency power, the antenna 102 transmits microwaves by the output high-frequency power.
(Step S2)
The microwave transmitted from the antenna 102 is applied to the site where the pressure ulcer is detected in the patient PA. The microwave is applied to the site where the pressure ulcer is detected, and the irradiated microwave is reflected by the pressure ulcer to generate a reflected wave. The antenna 102 captures the reflected wave, and the captured reflected wave generates high-frequency power. The antenna 102 outputs the generated high frequency power to the control device 110.
(Step S3)
The detection unit 133 acquires the patient PA identification information output by the processing unit 132. The antenna processing unit 115 down-converts the high-frequency power output by the antenna 102, and digitizes the down-converted high-frequency power. The antenna processing unit 115 outputs the result of digitizing the down-converted high-frequency power to the detection unit 133. The detection unit 133 acquires the result of digitizing the down-converted high-frequency power output by the antenna processing unit 115, and derives the reflection coefficient based on the result of digitizing the acquired down-converted high-frequency power. The detection unit 133 detects a pressure ulcer based on the derived reflection coefficient.
(Step S4)
The detection unit 133 outputs information indicating whether or not a pressure ulcer has been detected to the output unit 134.
The output unit 134 acquires information indicating whether or not the pressure ulcer output by the detection unit 133 has been detected, and processes the information indicating whether or not the acquired pressure ulcer has been detected to display the pressure ulcer on the display unit 140. Display whether or not it was detected.

In the above-described embodiment, the case where the antenna 102 and the control device 110 are connected by the feeder line 104 has been described, but the present invention is not limited to this example. For example, the antenna 102 and the control device 110 may be integrated.
In the above-described embodiment, the case of the 10 GHz band has been described as an example of the frequency of the microwave emitted by the antenna 102, but the present invention is not limited to this example. For example, the frequency is not limited to the 10 GHz band, and may be a frequency around the resonance frequency. Further, the antenna processing unit 115 may switch the frequency of the microwave transmitted by the antenna 102 by switching the frequency of the high frequency power.
In the above-described embodiment, the case where the sacral region is used as an example of a site for detecting a pressure ulcer has been described, but the present invention is not limited to this example. For example, a part other than the sacral part such as the calcaneus part, the greater trochanter part, and the ilium part may be a part for detecting a pressure ulcer.
In the above-described embodiment, the antenna 102 may be composed of a patch antenna containing conductive fibers. In this case, the antenna 102 may use a conductive cloth for the radiation conductor and the ground conductor. As the conductive fiber, a synthetic resin cloth containing polyester fiber, aramid fiber, or the like having a nickel layer on the surface of the copper coating may be used. With this configuration, the antenna 102 can be made flexible, so that the antenna 102 can be easily installed.
According to the present embodiment, the pressure ulcer detection device 100 microwaves from the antenna 102 installed between the bed 30 and the mattress 20 to the pressure ulcer detection site under the pressure ulcer detection site of the patient PA. To send. The pressure ulcer detection device 100 detects a pressure ulcer based on the reflected wave generated by the transmitted microwave being reflected by the pressure ulcer. Since the antenna 102 can be installed between the bed 30 and the mattress 20, the occurrence of pressure ulcers can be monitored without deteriorating the sleeping comfort of the patient PA.
By installing the antenna 102 on the mattress 20 under the site where the pressure ulcer of the patient PA lying down is detected, the patient PA and the antenna 102 do not come into direct contact with each other, so that the sensor such as the antenna 102 is used by the patient. Since it is possible to eliminate concerns about skin diseases and metal allergies caused by touching PA, it is possible to reduce the burden on users such as nurses and caregivers. In addition, since pressure ulcers can be detected without contact, it is hygienic and enables long-term monitoring of patient PA. Since it transmits microwaves and uses the reflected waves of the microwaves, it can detect pressure ulcers in a non-invasive manner.

(Modified Example 1 of the Embodiment)
(Decubitus ulcer detection device)
FIG. 1 can be applied to the pressure ulcer detection device 100a of the first modification of the embodiment. The pressure ulcer detection device 100a includes an antenna 102 and a control device 110a. The antenna 102, the control device 110, and a are connected by a feeder line 104. The pressure ulcer detection device 100a differs from the pressure ulcer detection device 100 in that it detects the stage of the pressure ulcer in addition to the detection of the pressure ulcer.

The user installs the antenna 102 under the site where the pressure ulcer is detected in the patient PA, and operates the control device 110a to detect the pressure ulcer. By this operation, high frequency power is supplied from the control device 110a to the antenna 102 via the feeding line 104.
The antenna 102 transmits microwaves by the high frequency power supplied by the control device 110a. The microwave transmitted from the antenna 102 is applied to the site where the pressure ulcer is detected in the patient PA. The microwave is applied to the site where the decubitus is detected, and the irradiated microwave is reflected by the decubitus to generate a reflected wave, and the reflected wave is captured by the antenna 102. The high-frequency power generated by the antenna 102 capturing the reflected wave is supplied from the antenna 102 to the control device 110a.
The control device 110a detects the pressure ulcer based on the high frequency power supplied by the antenna 102. The control device 110a derives the stage of the pressure ulcer based on the high frequency power. The control device 110a outputs a pressure ulcer detection result and, when the pressure ulcer is detected, information indicating the stage.
Hereinafter, among the antenna 102 included in the pressure ulcer detection device 100a and the control device 110a, the control device 110a different from the embodiment will be described.

FIG. 8 is a block diagram showing an example of a pressure ulcer detection device according to a modification of the first embodiment.
(Control device 110a)
The control device 110a is realized by a device such as a personal computer, a server, a smartphone, a tablet computer, or an industrial computer.
In the control device 110a, for example, the antenna processing unit 115, the storage unit 120a, the information processing unit 130a, the display unit 140, the operation unit 160, the power supply unit 170, and each component are shown in FIG. It is provided with a bus line 150 such as an address bus and a data bus for electrically connecting as described above.

The storage unit 120a stores the program 121 executed by the information processing unit 130a and the application 122a. Further, the reflection coefficient information 123 is stored in the storage unit 120a.
The application 122a includes the following modules in addition to the modules included in the application 122 described in the embodiment. The application 122a includes a module that causes the control device 110a to derive the stage of the pressure ulcer when the pressure ulcer is detected. The application 122a includes a module that causes the control device 110a to output a pressure ulcer detection result and information indicating the stage of the pressure ulcer when the pressure ulcer is detected.

The information processing unit 130a is a software function unit realized by, for example, a processor such as a CPU executing a program 121 stored in the storage unit 120a and an application 122a. All or part of the information processing unit 130a may be realized by hardware such as LSI, ASIC, or FPGA, or may be realized by a combination of software function unit and hardware.
The information processing unit 130a functions as, for example, a reception unit 131, a processing unit 132, a detection unit 133a, an output unit 134, and a derivation unit 135.
The detection unit 133a has the following functions in addition to the functions of the detection unit 133 described in the embodiment. When the pressure ulcer is detected, the detection unit 133a outputs the information indicating that the pressure ulcer is detected, the information indicating the reflection coefficient, and the identification information of the patient PA to the derivation unit 135.
The derivation unit 135 acquires the information indicating that the pressure ulcer is detected, the information indicating the reflection coefficient, and the identification information of the patient PA output by the detection unit 133a. The derivation unit 135 derives the stage of the pressure ulcer based on the acquired information indicating the reflectance coefficient. The derivation unit 135 outputs the derivation result of the pressure ulcer stage to the output unit 134.
The output unit 134 acquires information indicating whether or not the pressure ulcer output by the detection unit 133 has been detected, and processes the information indicating whether or not the acquired pressure ulcer has been detected to display the pressure ulcer on the display unit 140. Display information indicating whether or not it was detected. Further, when the output unit 134 acquires the derivation result of the pressure ulcer stage output by the derivation unit 135, the output unit 134 displays on the display unit 140 information indicating that the pressure ulcer has been detected and information indicating the pressure ulcer stage.

The process of deriving the stage of pressure ulcer will be described.
FIG. 9 is a diagram showing an example of the relationship between the stage of pressure ulcer and the difference in reflectance coefficient. In FIG. 9, the horizontal axis is the stage of the pressure ulcer, and the vertical axis is the difference in the reflectance coefficient. Here, the difference ΔS11 of the reflection coefficients is derived based on the equation (1).

ΔS11 = S11b (derived based on an example of a biological tissue model in which a pressure ulcer is occurring) -S11a (derived based on an example of a healthy biological tissue model) (1)

That is, the difference in reflection coefficient ΔS11 is derived by subtracting the reflection coefficient S11a derived based on an example of a healthy biological tissue model from the reflection coefficient S11b derived based on an example of a biological tissue model in which pressure ulcers occur. It was done.
Furthermore, FIG. 9 shows the relationship between the stage of the pressure ulcer and the difference in the reflectance coefficient for each of L = 10, 30, and 50.
According to FIG. 9, when L = 10, it can be seen that the ΔS11 of the stage II is increased as compared with the ΔS11 of the stage I. Further, it can be seen that the ΔS11 of the stage III and the ΔS11 of the stage IV have the same values as the ΔS11 of the stage II.
When L = 30 and 50, it can be seen that the ΔS11 of the stage II is increased as compared with the ΔS11 of the stage I. Further, it can be seen that the ΔS11 of the stage III is increased as compared with the ΔS11 of the stage II. It can be seen that the ΔS11 of the stage IV has the same value as the ΔS11 of the stage III.
From the above, it can be seen that when the area of the XY plane having a defect range of 212 m such as L = 10 (hereinafter referred to as “damaged area”) is narrow, it is possible to distinguish between stage I and stage II to stage IV. .. Further, when the damaged area is larger than L = 10 such as L = 30 and 50, it is possible to distinguish between stage I and stage II and between stage II and stage III to stage IV. I understand.

In the first modification of the present embodiment, when the derivation unit 135 acquires the patient PA identification information output by the detection unit 133a and the information indicating the reflection coefficient, the derivation unit 135 is based on the acquired patient PA identification information. From the reflection coefficient information 123 of the storage unit 120a, a table corresponding to the identification information of the patient PA is acquired. The derivation unit 135 acquires information indicating the reflection coefficient included in the acquired table. Here, the derivation unit 135 acquires information indicating the reflection coefficient derived when the person is healthy from the table. However, the derivation unit 135 may acquire the information indicating the oldest reflection coefficient when there is no information indicating the reflection coefficient derived when the person is healthy. The derivation unit 135 derives the difference between the reflection coefficient acquired from the detection unit 133a and the reflection coefficient acquired from the table.
The derivation unit 135 determines the difference in reflectance coefficient based on the reflectance coefficient difference threshold value, which is the threshold value of the difference in reflectance coefficient that distinguishes stage I from stage II and stage IV when the damaged area is less than the damaged area threshold value. If is less than the reflectance difference threshold, stage I is detected, and if the reflectance difference is greater than or equal to the reflectance difference threshold, either stage II to stage IV is detected. Here, the damaged area threshold value is preset in the derivation unit 135 based on the value of L. The reflectance coefficient difference threshold is preset in the derivation unit 135 based on the difference in the reflectance coefficient of the stage I and the difference in the reflectance coefficient from the stage II to the stage IV. The reflectance coefficient difference threshold value may differ depending on the site where the pressure ulcer is detected and the value of L.
When the damaged area is equal to or larger than the damaged area threshold, the derivation unit 135 has a first reflection coefficient difference threshold which is a threshold of the difference between the reflection coefficients that distinguishes the stage I and the stage II, and the stage II and the stage III. Based on the second reflection coefficient difference threshold, which is the threshold for the difference in reflection coefficient that distinguishes it from stage IV, if the difference in reflection coefficient is less than the first reflection coefficient difference threshold, it is assumed that stage I is detected and reflection is performed. If the difference in coefficients is greater than or equal to the first reflectance coefficient difference threshold and less than or equal to the second reflectance coefficient difference threshold, stage II is detected, and if the reflectance difference is greater than or equal to the second reflectance coefficient difference threshold. Suppose that any of stage III to stage IV is detected. Here, the damaged area threshold value is preset in the derivation unit 135 based on the value of L. The first reflectance coefficient difference threshold is preset in the derivation unit 135 based on the difference in the reflectance coefficient of the stage I and the difference in the reflectance coefficient of the stage II. The second reflection coefficient difference threshold is preset in the derivation unit 135 based on the difference in the reflection coefficient of the stage II and the difference in the reflection coefficient of the stage III. Each of the first reflectance coefficient difference threshold value and the second reflectance coefficient difference threshold value may be different depending on the site where the pressure ulcer is detected.

(Operation of pressure ulcer detection device)
FIG. 10 is a flowchart showing an example of the operation of the pressure ulcer detection device according to the first modification of the embodiment. In FIG. 10, the patient PA lies on the mattress 20 placed on the bed 30 with the head resting on the pillow 10, under the site where the pressure ulcer of the patient PA is detected, and the bed 30 and the mattress. The operation after the user installs the antenna 102 is shown between the 20 and the 20.
From step S11 to step S13, steps S1 to S3 of FIG. 7 described above can be applied.
(Step S14)
The detection unit 133a outputs information indicating whether or not a pressure ulcer has been detected to the output unit 134. When the pressure ulcer is detected, the detection unit 133a outputs the information indicating that the pressure ulcer is detected, the information indicating the reflection coefficient, and the identification information of the patient PA to the derivation unit 135.
The derivation unit 135 acquires the information indicating that the pressure ulcer is detected, the information indicating the reflection coefficient, and the identification information of the patient PA output by the detection unit 133a. The derivation unit 135 derives the stage of the pressure ulcer based on the acquired information indicating the reflectance coefficient. The derivation unit 135 outputs the derivation result of the pressure ulcer stage to the output unit 134.
(Step S15)
The output unit 134 acquires information indicating whether or not the pressure ulcer output by the detection unit 133 has been detected, and processes the information indicating whether or not the acquired pressure ulcer has been detected to display the pressure ulcer on the display unit 140. Display information indicating whether or not it was detected. Further, when the output unit 134 acquires the derivation result of the pressure ulcer stage output by the derivation unit 135, the output unit 134 displays on the display unit 140 information indicating that the pressure ulcer has been detected and information indicating the pressure ulcer stage.

In the first modification of the above-described embodiment, the case of distinguishing the stage IV from the stage I and the stage II and the case of distinguishing the stage I from the stage II and the stage II and the stage III from the stage IV have been described. Not limited to examples. For example, in order to identify either stage II to stage IV, if it is difficult to judge by a specific frequency due to individual differences, damage range, etc., select an appropriate frequency to select either stage I to stage IV. Can be identified.
According to the first modification of the present embodiment, the pressure ulcer detection device 100a is a site for detecting a pressure ulcer from an antenna 102 installed between a bed 30 and a mattress 20 under a site for detecting a pressure ulcer in a patient PA. Microwave is transmitted to. The pressure ulcer detection device 100a detects a pressure ulcer based on the reflected wave generated by the transmitted microwave reflected by the pressure ulcer, and detects the stage when the pressure ulcer is detected. With this configuration, in addition to the effect of the embodiment, information indicating the degree of pressure ulcer such as the stage of pressure ulcer can be acquired, so that more detailed information can be acquired.

(Modification 2 of the embodiment)
(Decubitus ulcer detection device)
The pressure ulcer detection device 100b of the modified example of the embodiment is different from the pressure ulcer detection device 100 in that it includes a plurality of antennas.
FIG. 11 is a block diagram showing an example of a pressure ulcer detection device according to a modification of the second embodiment.
The pressure ulcer detection device 100b includes an antenna 102a, an antenna 102b, and a control device 110b. The antenna 102a and the control device 110b are connected via a feeder line 104a, and the antenna 102b and the control device 110b are connected via a feeder line 104b.

The user installs each of the antenna 102a and the antenna 102b under the site where the pressure ulcer is detected in the patient PA, and operates the control device 110b to detect the pressure ulcer. By this operation, high-frequency power is supplied from the control device 110b to each of the antenna 102a and the antenna 102b via each of the feeder line 104a and the feeder line 104b.
Each of the antenna 102a and the antenna 102b transmits microwaves by the high frequency power supplied by the control device 110b. The microwaves transmitted from each of the antenna 102a and the antenna 102b are applied to the site where the pressure ulcer is detected in the patient PA. The microwave is applied to the site where the decubitus is detected, and the irradiated microwave is reflected by the decubitus to generate a reflected wave, and the reflected wave is captured by the antenna 102a and the antenna 102b, respectively. The high-frequency power generated by each of the antenna 102a and the antenna 102b capturing the reflected wave is supplied to the control device 110b from each of the antenna 102a and the antenna 102b.
The control device 110b detects the pressure ulcer based on the high frequency power supplied by each of the antenna 102a and the antenna 102b. The control device 110 outputs a pressure ulcer detection result.
Hereinafter, the antenna 102a included in the pressure ulcer detection device 100b, the antenna 102b, and the control device 110b will be sequentially described.

Since the antenna 102a and the antenna 102b have the same configuration as the antenna 102 described in the embodiment, the description thereof is omitted here. However, the antenna 102a and the antenna 102b may be different in size from the antenna 102. Further, the size of the antenna 102a and the size of the antenna 102b may be different.

(Control device 110b)
The control device 110b is realized by a device such as a personal computer, a server, a smartphone, a tablet computer, or an industrial computer.
In the control device 110b, for example, the antenna processing unit 115b, the storage unit 120b, the information processing unit 130b, the display unit 140, the operation unit 160, the power supply unit 170, and each component are shown in FIG. It is provided with a bus line 150 such as an address bus and a data bus for electrically connecting as described above.
The antenna processing unit 115b is realized by including a power feeding module and a network analyzer. The antenna processing unit 115b supplies high-frequency power to the feeding unit 109a of the antenna 102a via the feeding line 104a under the control of the information processing unit 130b. The antenna processing unit 115b supplies high-frequency power to the feeding unit 109b of the antenna 102b via the feeding line 104b under the control of the information processing unit 130b. The antenna processing unit 115b acquires the high-frequency power output by the antenna 102a, down-converts the acquired high-frequency power, and digitizes the down-converted high-frequency power. The antenna processing unit 115b outputs the result of digitizing the down-converted high-frequency power to the information processing unit 130b. The antenna processing unit 115b acquires the high-frequency power output by the antenna 102b, down-converts the acquired high-frequency power, and digitizes the down-converted high-frequency power. The antenna processing unit 115b outputs the result of digitizing the down-converted high-frequency power to the information processing unit 130b.

Specifically, the antenna processing unit 115b acquires information indicating that power is supplied to the power supply unit 109a output by the information processing unit 130b, and the antenna 102a is based on the information indicating that power is supplied to the acquired power supply unit 109a. Power to. The antenna processing unit 115b acquires information indicating that power is supplied to the power feeding unit 109b output by the information processing unit 130b, and supplies power to the antenna 102b based on the information indicating that power is supplied to the acquired power feeding unit 109b.

The storage unit 120b stores the program 121 executed by the information processing unit 130b and the application 122b. Further, the reflection coefficient information 123b is stored in the storage unit 120b.
The application 122b includes a module that causes the control device 110b to transmit microwaves to the antenna 102a by supplying high-frequency power to the feeding unit 109a of the antenna 102a. The application 122b includes a module that causes the control device 110b to transmit microwaves to the antenna 102b by supplying high frequency power to the feeding unit 109b of the antenna 102b. The application 122b includes a module for causing the control device 110b to receive the reflected wave of the microwave transmitted to the antenna 102a. The application 122b includes a module for causing the control device 110b to receive the reflected wave of the microwave transmitted to the antenna 102b. The app 122b includes a module for causing the control device 110b to detect decubitus based on each of the reflected wave of the microwave transmitted to the received antenna 102a and the reflected wave of the microwave transmitted to the antenna 102b. .. The application 122b includes a module that causes the control device 110b to output a pressure ulcer detection result.

Reflection coefficient information 123b will be described.
FIG. 12 is a diagram showing an example of reflectance coefficient information. The reflectance coefficient information 123b is based on the date and time when the pressure ulcer detection device 100 performs the process of detecting the pressure ulcer for each patient identification information and the reflected wave of the microwave transmitted to the site where the pressure ulcer is detected on that date and time. This is tabular information associated with the result of deriving. Here, the result of deriving the reflection coefficient is the reflection coefficient A, which is the result of deriving based on the reflected wave of the microwave transmitted by the antenna 102a, and the result derived based on the reflected wave of the microwave transmitted by the antenna 102b. The resulting reflection coefficient B is included. In the example shown in FIG. 12, the date and time "***** year *** month ** day" is associated with the reflection coefficient A "***" and the reflection coefficient B "++++" with respect to the patient identification information "AAA001". The date and time "++++ year ++ month ++ day" is associated with the reflection coefficient A "++++" and the reflection coefficient B "***", and the date and time "#### year ## month ## day" and the reflection coefficient A “***” and the reflection coefficient B “+++” are associated with each other. It is preferable that the reflection coefficient information 123b stores the date and time and the association between the reflection coefficient A and the reflection coefficient B even before the pressure ulcer is detected. The explanation will be continued by returning to FIG.

The information processing unit 130b is a software function unit realized by, for example, a processor such as a CPU executing a program 121 stored in the storage unit 120b and an application 122b. All or part of the information processing unit 130b may be realized by hardware such as LSI, ASIC, or FPGA, or may be realized by a combination of software function unit and hardware.
The information processing unit 130b functions as, for example, a reception unit 131, a processing unit 132b, a detection unit 133b, and an output unit 134.

The processing unit 132b acquires information indicating that the pressure ulcer output by the reception unit 131 is detected. Based on the information indicating that the acquired pressure ulcer is detected, the processing unit 132b provides the antenna processing unit 115b with information A indicating that power is supplied to the power feeding unit 109a and information B indicating that power is supplied to the power feeding unit 109b. Is output. For example, the processing unit 132b may sequentially output the information A and the information B to the antenna processing unit 115b. In addition, the processing unit 132b acquires the identification information of the patient PA from the information indicating that the pressure ulcer is detected, and outputs the information indicating the acquired patient PA to the detection unit 133b.
The detection unit 133b acquires the patient PA identification information output by the processing unit 132b. The detection unit 133b acquires the result of digitizing the down-converted high-frequency power output by the antenna processing unit 115b by outputting the information A by the processing unit 132b, and is based on the result of digitizing the acquired down-converted high-frequency power. Then, the reflection coefficient A is derived. The detection unit 133b detects a pressure ulcer based on the derived reflection coefficient A. The detection unit 133b acquires the result of digitizing the down-converted high-frequency power output by the antenna processing unit 115b by outputting the information B by the processing unit 132b, and is based on the result of digitizing the acquired down-converted high-frequency power. Then, the reflection coefficient B is derived. The detection unit 133b detects a pressure ulcer based on the derived reflection coefficient B. The detection unit 133b acquires a table corresponding to the acquired identification information of the patient PA from the reflection coefficient information 123b, and the date and time when the reflection coefficient A and the reflection coefficient B are derived from the acquired table, and the derived reflection coefficient. A and the reflection coefficient B are associated and stored. It is assumed that the detection unit 133b has detected a pressure ulcer when the derived reflection coefficient A is equal to or more than the reflection coefficient threshold value, and has not detected a pressure ulcer when the reflected reflection coefficient A is less than the reflection coefficient threshold value. It is assumed that the detection unit 133b has detected a pressure ulcer when the derived reflection coefficient B is equal to or more than the reflection coefficient threshold value, and has not detected a pressure ulcer when the reflected reflection coefficient B is less than the reflection coefficient threshold value. The detection unit 133 outputs information indicating whether or not a pressure ulcer has been detected to the output unit 134 at each of the site for detecting the pressure ulcer on the antenna 102a and the site for detecting the pressure ulcer on the antenna 102b.

(Operation of pressure ulcer detection device)
FIG. 13 is a flowchart showing an example of the operation of the pressure ulcer detection device according to the second modification of the embodiment. In FIG. 13, the patient PA lies on the mattress 20 placed on the bed 30 with the head resting on the pillow 10, under the site where the pressure ulcer of the patient PA is detected, and the bed 30 and the mattress. The operation after the user installs the antenna 102a and the antenna 102b is shown between the 20 and the 20. The position where the antenna 102a is installed is different from the position where the antenna 102b is installed.
(Step S21)
The reception unit 131 receives information indicating that the pressure ulcer output by the operation unit 160 is detected by the user inputting the identification information of the patient PA to the operation unit 160 and performing an operation for detecting the pressure ulcer. The reception unit 131 outputs information indicating that the received pressure ulcer is detected to the processing unit 132b.
The processing unit 132b acquires information indicating that the pressure ulcer is detected, which is output by the reception unit 131, and supplies power to the antenna processing unit 115b to the power feeding unit 109a based on the information indicating that the acquired pressure ulcer is detected. Outputs information indicating. In addition, the processing unit 132b acquires the identification information of the patient PA from the information indicating that the pressure ulcer is detected, and outputs the information indicating the acquired patient PA to the detection unit 133b.
The antenna processing unit 115b acquires information indicating that power is supplied to the power feeding unit 109a output by the processing unit 132b, and outputs high-frequency power to the antenna 102a based on the information indicating that power is supplied to the acquired power feeding unit 109a. .. When the control device 110b outputs high-frequency power, the antenna 102a transmits microwaves by the output high-frequency power.
(Step S22)
The microwave transmitted from the antenna 102a is applied to the site where the pressure ulcer is detected in the patient PA. The microwave is applied to the site where the pressure ulcer is detected, and the irradiated microwave is reflected by the pressure ulcer to generate a reflected wave. The antenna 102a captures the reflected wave, and the captured reflected wave generates high-frequency power. The antenna 102a outputs the generated high frequency power to the control device 110b.
(Step S23)
The detection unit 133b acquires the patient PA identification information output by the processing unit 132b. The detection unit 133b acquires the result of digitizing the down-converted high-frequency power output by the antenna processing unit 115b, and based on the result of digitizing the acquired down-converted high-frequency power, detects the pressure ulcer on which the antenna 102a is installed. Detect pressure ulcers at the site to be detected.
(Step S24)
The detection unit 133b outputs information indicating whether or not the pressure ulcer is detected to the output unit 134 at the site where the pressure ulcer is detected on the antenna 102a.
The output unit 134 acquires information indicating whether or not the pressure ulcer output by the detection unit 133b has been detected, and processes the information indicating whether or not the acquired pressure ulcer has been detected to display the antenna 102a on the display unit 140. On the site where the pressure ulcer is detected, whether or not the pressure ulcer is detected is displayed.

(Step S25)
The processing unit 132b outputs information indicating that power is supplied to the power feeding unit 109b to the antenna processing unit 115b.
The antenna processing unit 115b acquires information indicating that power is supplied to the power feeding unit 109b output by the processing unit 132b, and outputs high-frequency power to the antenna 102b based on the information indicating that power is supplied to the acquired power feeding unit 109b. .. When the control device 110b outputs high-frequency power, the antenna 102b transmits microwaves by the output high-frequency power.
(Step S26)
The microwave transmitted from the antenna 102b is applied to the site where the pressure ulcer is detected in the patient PA. The microwave is applied to the site where the pressure ulcer is detected, and the irradiated microwave is reflected by the pressure ulcer to generate a reflected wave. The antenna 102b captures the reflected wave, and the captured reflected wave generates high-frequency power. The antenna 102b outputs the generated high frequency power to the control device 110b.
(Step S27)
The detection unit 133b acquires the result of digitizing the down-converted high-frequency power output by the antenna processing unit 115b, and based on the result of digitizing the acquired down-converted high-frequency power, detects the pressure ulcer on which the antenna 102b is installed. Detect pressure ulcers at the site to be detected.
(Step S28)
The detection unit 133b outputs information indicating whether or not the pressure ulcer is detected to the output unit 134 at the site where the pressure ulcer is detected on the antenna 102b.
The output unit 134 acquires the information indicating whether or not the pressure ulcer output by the detection unit 133b is detected, and processes the information indicating whether or not the acquired pressure ulcer is detected, thereby displaying the antenna 102b on the display unit 140. On the site where the pressure ulcer is detected, whether or not the pressure ulcer is detected is displayed.
In the second modification of the above-described embodiment, the case where the pressure ulcer detection device 100b includes two antennas, the antenna 102a and the antenna 102b, has been described, but the present invention is not limited to this example. For example, the pressure ulcer detection device 100b may include three or more antennas. In this case, control may be performed to sequentially transmit microwaves from a plurality of antennas. With this configuration, it is possible to detect pressure ulcers at three or more sites where pressure ulcers are detected.
In the second modification of the above-described embodiment, the case where the pressure ulcer detection device 100 of the embodiment is provided with a plurality of antennas has been described, but the present invention is not limited to this example. For example, the pressure ulcer detection device 100a of the first modification of the embodiment may be provided with a plurality of antennas.
In the second modification of the above-described embodiment, the case where the antenna 102a and the control device 110b are connected via the feeder line 104a and the antenna 102b and the control device 110b are connected via the feeder line 104b has been described. , Not limited to this example. For example, either one or both of the antenna 102a and the antenna 102b may be integrated with the control device 110b.
According to the second modification of the present embodiment, the pressure ulcer detection device 100b is a combination of an antenna 102a and an antenna 102b installed under a site for detecting a pressure ulcer in a patient PA and between a bed 30 and a mattress 20. Microwaves are transmitted from each to the site where the pressure ulcer is detected. The pressure ulcer detection device 100b detects a pressure ulcer based on the reflected wave generated by the transmitted microwave being reflected by the pressure ulcer. Since each of the antenna 102a and the antenna 102b can be installed between the bed 30 and the mattress 20, the occurrence of pressure ulcer can be monitored without deteriorating the sleeping comfort of the patient PA.
By installing each of the antenna 102a and the antenna 102b on the mattress 20 under the site where the pressure ulcer of the patient PA lying is detected, each of the patient PA, the antenna 102a, and the antenna 102b is directly installed. Since there is no touch, it is possible to eliminate concerns about skin diseases and metal allergies caused by the sensors such as the antenna 102a and the antenna 102b touching the patient PA, so that the burden on users such as nurses and caregivers can be reduced. In addition, since pressure ulcers can be detected without contact, it is hygienic and enables long-term monitoring of patient PA. Since it transmits microwaves and uses the reflected waves of the microwaves, it can detect pressure ulcers in a non-invasive manner. Further, by reducing the sizes of the antenna 102a and the antenna 102b, the accuracy of detecting the pressure ulcer can be improved.

<Configuration example>
As a configuration example, an antenna that transmits microwaves to a living body and receives reflected waves of the transmitted microwaves (antenna 102 in the embodiment), and a feeding unit that feeds the antenna (feeding unit 109 in the embodiment). , A decubitus detection device including a detection unit that detects decubitus based on a reflected wave received by an antenna and an output unit that outputs a detection result of decubitus detected by the detection unit.
As a configuration example, a derivation unit for detecting the degree of pressure ulcer based on the degree of attenuation of the reflected wave detected by the detection unit is provided, and the output unit outputs information indicating the degree of pressure ulcer detected by the derivation unit.
As an example of the configuration, the derivation unit derives the reflectance coefficient based on the reflected wave, and the derived reflection coefficient and the reflection coefficient derived based on the reflected wave obtained when the microwave is transmitted to a healthy living body. The degree of decubitus is detected based on.
As a configuration example, the antenna is a patch antenna containing conductive fibers.
As a configuration example, an antenna processing unit that switches the frequency of the microwave transmitted by the antenna is provided, and the antenna transmits the microwave to the living body based on the frequency switched by the antenna processing unit.
As a configuration example, the antenna includes a plurality of antennas (in the embodiment, the antenna 102a and the antenna 102b), the feeding unit feeds each of the plurality of antennas, and each of the antennas transmits microwaves to the living body. Then, the detection unit detects the decubitus based on the reflected wave of the microwave transmitted by each of the plurality of antennas, and the output unit outputs the detection result of the decubitus detected by the detection unit.

Although the embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, changes, and combinations can be made without departing from the gist of the invention. These embodiments and variations thereof are included in the scope and gist of the invention, and at the same time, are included in the scope of the invention described in the claims and the equivalent scope thereof.
The control device 110, the control device 110a, and the control device 110b described above have a computer inside. The process of each process of each device described above is stored in a computer-readable recording medium in the form of a program, and the process is performed by the computer reading and executing this program. Here, the computer-readable recording medium refers to a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like. Further, this computer program may be distributed to a computer via a communication line, and the computer receiving the distribution may execute the program.
Further, the above program may be for realizing a part of the above-mentioned functions.
Further, it may be a so-called difference file (difference program) that can realize the above-mentioned function in combination with a program already recorded in the computer system.

10 ... Pillow, 20 ... Mattress, 30 ... Bed, 100, 100a, 100b ... Pressure ulcer detector, 102, 102a, 102b ... Antenna, 104, 104a, 104b ... Feed line, 106, 106a, 106b ... Radiant element, 107, 107a, 107b ... Dielectric substrate, 108, 108a, 108b ... Ground conductor plate, 109, 109a, 109b ... Feeding unit, 110, 110a, 110b ... Control device, 115 ... Antenna processing unit, 120, 120a, 120b ... Storage unit , 121 ... Program, 122, 122a, 122b ... App, 123, 123b ... Reflection coefficient information, 130, 130a, 130b ... Information processing unit, 131 ... Reception unit, 132, 132b ... Processing unit, 133, 133a, 133b … Detection unit, 134… Output unit, 135… Derivation unit 140… Display unit, 150… Bus line, 160… Operation unit, 170… Power supply unit, 202, 202m… Bone, 204, 204m… Muscle layer, 206, 206m… Fat layer, 208, 208 m ... skin layer, 210, 210 m ... blood layer, 212 m ... defect range, 220 m ... air layer

Claims (5)

An antenna that transmits microwaves to a living body and receives the reflected waves of the transmitted microwaves.
A power supply unit that supplies power to the antenna and
A detection unit that detects pressure ulcers based on the reflected wave received by the antenna,
The reflection coefficient is derived based on the reflected wave detected by the detection unit, and is based on the derived reflection coefficient and the reflection coefficient derived based on the reflected wave obtained when the microwave is transmitted to a healthy living body. And the derivation part that derives the degree of decubitus,
It is provided with an output unit that outputs information indicating the degree of pressure ulcer derived by the derivation unit .
The antenna, Ru is installed in the living body and non-contact, pressure ulcers detector. The pressure ulcer detection device according to claim 1, wherein the antenna is a patch antenna containing conductive fibers. It is equipped with an antenna processing unit that switches the frequency of microwaves transmitted by the antenna.
The pressure ulcer detection device according to claim 1 or 2 , wherein the antenna transmits microwaves to the living body based on the frequency switched by the antenna processing unit. The antenna comprises a plurality of antennas.
The feeding unit supplies power to each of the plurality of antennas.
Each of the antennas transmits microwaves to the living body and
The detection unit detects a pressure ulcer based on the reflected wave of the microwave transmitted by each of the plurality of antennas.
The pressure ulcer detection device according to any one of claims 1 to 3 , wherein the output unit outputs the detection result of the pressure ulcer detected by the detection unit. Steps to power the antenna and
The step of transmitting microwaves to the living body and
The step of receiving the reflected wave of the transmitted microwave and
A step of detecting a pressure ulcer based on the reflected wave received by the antenna,
The degree of decubitus is determined based on the reflection coefficient derived by deriving the reflection coefficient based on the reflected wave and the reflected coefficient derived based on the reflected wave obtained when the microwave is transmitted to a healthy living body. Steps to derive and
Possess and outputting information indicating the degree of pressure ulcers derived in the step of deriving,
The antenna, the biological and Ru is installed in a non-contact, pressure sores detecting method decubitus detecting apparatus executes.

Images