WO2010106597A1

WO2010106597A1 - Signal generating device for respiratory synchronization and body movement detection sensor unit

Info

Publication number: WO2010106597A1
Application number: PCT/JP2009/006301
Authority: WO
Inventors: 武藤昭男; 秋山守人; 福田修
Original assignee: 株式会社ホンダ・ハドロニクス; 独立行政法人産業技術総合研究所
Priority date: 2009-03-19
Filing date: 2009-11-24
Publication date: 2010-09-23
Also published as: JP2012110355A

Abstract

Provided is a body movement detection sensor unit capable of accurately detecting the body movement due to the respiration of a patient, which has high durability, does not obstruct photographing, and requires no skill. A body movement detection sensor unit (11) is configured from a first case (21) serving as a pressure part, a thin film sensor element (23), and a second case (22) containing the thin film sensor (23). The first and second cases (21, 22) are communicated with each other by a breathing tube (25), and silicon oil (27) is sealed therein. The body movement detection sensor unit (11) is provided to a bed (3), and the pressure part (21) is inserted between the back side of the patient and a table (8) so as to detect the body movement.

Description

Respiratory synchronization signal generation device and body motion detection sensor unit

The present invention is controlled based on a respiratory synchronization signal input from the outside, and is capable of suppressing the influence of body movement due to respiration, a CT scanning device, a PET device, a radiation therapy simulation device, a radiation The present invention relates to a respiratory synchronization signal generation device capable of generating and outputting the respiratory synchronization signal to a medical device such as a treatment device, and a body motion detection sensor unit that detects a respiratory motion.

A so-called tomography device is well known as a medical device that can take a tomographic image of a human body cut at an arbitrary part. A CT scan device that takes an image by exposing X-rays, and a patient is given a radioactive tracer. A PET apparatus that detects and captures gamma rays emitted from a radioactive tracer is known. In addition, medical equipment in which a predetermined device is added to a tomographic apparatus is also known, and so-called radiation therapy simulation apparatuses, radiation therapy apparatuses, and the like are known. The radiotherapy simulation apparatus is an apparatus that can take a tomographic image of a patient and perform a radiotherapy simulation based on the acquired tomographic image, thereby making a treatment plan. The radiotherapy apparatus is an apparatus that irradiates an affected area with radiation by an operator operating the apparatus based on a radiotherapy plan.

As is well known in the art, the CT scanning apparatus is composed of a gantry having an opening with a predetermined inner diameter penetrating the center, a bed on which a patient lies, and a computer for processing data. Inside the gantry, an X-ray source that emits X-rays and a detector array composed of a large number of sensors that detect X-rays transmitted through the human body are arranged at positions facing each other across the opening. The radiation source and the detector array can be rotated in the circumferential direction around the opening. Then, the opening is configured so that a patient who is supine on the bed is inserted together with the bed. When a tomographic image is obtained with such a CT scanning apparatus, a patient who is lying on the bed by driving the bed is inserted into the opening of the gantry, and a predetermined region to be imaged is located in the X-ray exposure field. Like that. Then, while rotating the X-ray source and the detector array, X-rays are emitted from different directions, and the X-ray transmitted through the human body is detected by the detector array. When the data detected in this way is processed in an integrated manner by a computer, one tomographic image is obtained.

In the tomography apparatus, the bed is driven to move the region to be imaged little by little, and a plurality of tomographic images are captured. If it does so, the site | part of imaging | photography object can be imaged in three dimensions. By the way, when taking a tomographic image, the patient is careful not to move on the bed, but the patient moves due to a slight movement, that is, a body movement due to a breathing movement or heartbeat. If the patient moves due to body movement, a shift occurs between a plurality of tomographic images to be photographed, so that a three-dimensional tomographic image cannot be obtained clearly. If it does so, a tumor cannot be overlooked in a diagnosis, or the position of a tumor cannot be pinpointed correctly. In addition, it is impossible to appropriately design a treatment plan in the radiotherapy simulation apparatus, and in the radiotherapy apparatus, a healthy tissue other than a tumor may be accidentally irradiated with radiation to be damaged.

A tomographic method for obtaining a clear tomographic image by collecting data with little deviation by controlling the tomographic apparatus in synchronism with the movement of the breath and the heartbeat and minimizing the influence of body movement. When performing such a tomography method, it is necessary to detect the body movement of the human body and transmit it to the tomography apparatus. Patent Document 1 describes a CT scan device that obtains a heart beat synchronization signal by an electrocardiogram detection sensor affixed to a patient's chest and images a tomographic image of the heart. According to the CT scanning device described in Patent Document 1, since the CT scanning device is controlled in synchronization with the heartbeat, a tomographic image can be taken without being affected by the heartbeat, and a clear tomographic image of the heart can be obtained. can get. However, since the breathing operation is not taken into consideration, if a tomographic image of a part other than the heart is captured, the tomographic image becomes blurred due to the breathing motion. It is necessary to detect a respiratory action and transmit a synchronization signal to the tomography apparatus. Known methods for detecting the movement of breathing include, for example, a method for detecting vertical movement of the chest, a method for detecting expansion and contraction of the abdomen, and a method for detecting skin tension. The method of detecting the vertical movement of the chest includes a method using a marker and a method using a measuring rod. The method using the marker detects the vertical movement of the chest by monitoring the marker attached to the chest of the patient with an external CCD camera. In the method using a measuring rod, one end of the measuring rod is brought into contact with the patient's chest, a fulcrum of the measuring rod is provided near the patient, and the vertical movement of the chest is amplified at the other end. It is a method to detect. The method for detecting the expansion and contraction of the abdomen is a method for detecting the expansion and contraction of the abdomen by detecting the change in the tension of the belt wound around the abdomen or the air pressure in the hollow belt. Is a method in which a strain sensor is affixed to the patient's body surface and the tension of the skin is detected to detect breathing motion.

JP 2001-61835 A JP 2001-187030 A

Patent Document 2 describes a sheet-like piezoelectric sensor that is provided on a bed on which a patient lies, and that can detect body movements due to breathing motion by contacting the patient's back. The piezoelectric sensor described in Patent Document 2 is a sensor having a so-called laminated structure in which a pressure detection element made of a PVDF film or an aluminum nitride thin film, that is, a sensor element is sandwiched between thin resin sheets, Body movement due to movement can be detected as a change in voltage.

If the above-described method for detecting a breathing motion is performed, or if the piezoelectric sensor described in Patent Document 2 is used, body movement due to the breathing motion can be detected. If the detected body movement signal is transmitted to the tomography apparatus, and the tomography apparatus scans synchronously based on the signal, a clear tomography that is not affected by the body movement due to breathing motion An image can be obtained. However, there are some problems to be solved. For example, in the case of a method using a marker, there is a problem of selecting a position where the marker is pasted. That is, when the marker is affixed to the patient's chest, it is necessary to affix the marker at a position that does not hinder the X-ray exposure and can ensure the stability of the marker. Furthermore, other problems arise because the marker is applied to the chest. That is, during tomographic imaging, the patient cannot wear a cold blanket, and when performing radiotherapy, the marker interferes with radiation irradiation. There is also a problem with the measurement method. In the measuring rod, the fixing tool for fixing the fulcrum hinders X-ray exposure, and the entire measuring rod may be reflected in the image. Furthermore, since the measuring rod protrudes to the outside, there is also a problem that it hits the gantry of the CT scanning device. There are also problems with the method of detecting abdominal expansion and contraction. That is, in a healthy person, both the diaphragm and intercostal muscles move actively during respiration, but in the case of a patient with weak physical strength, the diaphragm functions insufficiently and shallow breathing due to fine movement of the intercostal muscles increases. Then, even if the abdomen is inflated and contracted by a belt or the like, respiration may not be detected accurately. Moreover, if a patient is pressed with a belt, it will become a patient's stress. There is also a problem with the method of detecting the skin tension, and if the patient's skin is slack, the accuracy of detection becomes worse, and the communication signal line connected to the strain sensor gets in the way. .

When using the piezoelectric sensor described in Patent Document 2, many of the above problems are solved. For example, a piezoelectric sensor is provided on a bed on which the patient lies, and touches the patient's back to detect the movement of breathing. There is no such thing as hitting a photographic device. In addition, since the piezoelectric sensor is made of a PVDF film or an aluminum nitride thin film, it is relatively difficult to appear in a tomographic image. However, there is no guarantee that the piezoelectric sensor described in Patent Document 2 will not appear in the image at all depending on the configuration. There are also problems inherent to pressure sensing elements made of PVDF films or aluminum nitride thin films. That is, such a pressure detection element, that is, a sensor element has a problem that durability is not high. In the piezoelectric sensor described in Patent Document 2, the pressure detection element is sandwiched and protected by a thin resin sheet, and the durability is improved to some extent. However, when the pressure detection element is repeatedly pressed by the patient's back, the pressure detection element Will deteriorate early. If the thickness of the resin sheet sandwiching the pressure detection element is increased, the durability is improved, but another problem that the sensitivity of the sensor is lowered arises. In addition, a signal line for transmitting the detected voltage to the outside is provided in such a pressure detection element. However, since the pressure detection element is formed in a thin film shape, the junction between the pressure detection element and the signal line The strength of is weak and problematic. In the case of the piezoelectric sensor described in Patent Document 2, since the pressure detection element is directly placed on the patient's back to detect pressure fluctuation, the joint portion is damaged early and the signal line is disconnected. There is a high risk of losing. In addition, since aluminum nitride can generally be manufactured only in a small area, the back portion where the change in pressure can be detected becomes a small area, and depending on the portion to be contacted, the respiratory action cannot be detected reliably. . Furthermore, although the piezoelectric sensor described in Patent Document 2 is a sensor unit including a pressure detection element and a resin sheet covering the pressure detection element, this resin sheet is only for the purpose of protection. The structure is such that the pressure received by the resin sheet is transmitted to the entire pressure detecting element. That is, when viewed from the point of pressure detection, there is no substantial difference from a sensor composed of a single pressure detection element. In this case, the pressure received from the patient's back does not necessarily act uniformly on the pressure detection element, so that the pressure received by the pressure detection element may be uneven, and the sensor detection accuracy may not be sufficiently obtained. That is, depending on the position, area, and the like where the patient's back is in contact with the piezoelectric sensor, fluctuations in pressure due to patient movement may not be detected accurately.

The present invention has been made in view of the above-described problems. Specifically, the present invention does not appear in an image in tomography or interfere with radiotherapy, and does not collide with a tomography apparatus. An inexpensive and durable body motion detection sensor unit that has a configuration that can reliably detect body motion due to patient breathing and that can reliably detect body motion due to patient breathing without requiring skill, and this sensor unit To provide a respiratory synchronization signal generation device capable of generating a respiratory synchronization signal synchronized with the respiratory motion detected in step S1 and outputting the respiratory synchronization signal to a medical device such as a tomography apparatus or a radiotherapy apparatus It is an object.

In order to achieve the above object, the present invention provides a body motion detection sensor unit comprising: a hollow container that is flexible and has a generally flat sheet shape; and a PVDF stored in the container or another container The thin film sensor element is made of aluminum nitride or zinc oxide, and the fluid is hermetically or liquid-tightly sealed in these containers. And it is comprised so that the pressure which acts on a container may act on a thin film sensor element via a fluid, and may be detected. Further, such a container is inserted into the contact portion between the back surface of the patient and the table so that the area of the pressure receiving portion is larger than the area of the thin film sensor element. In another configuration of the present invention, the body motion detection sensor unit includes a hollow first container that is flexible and has a flat sheet shape, a hollow second container, and a hollow portion. A conduit connecting them so as to communicate with each other, a thin film sensor element made of PVDF, aluminum nitride, or zinc oxide stored in the second container, and hermetically or liquid tightly inside the container It is comprised from the enclosed fluid, and it comprises so that the pressure which acts on a 1st container may act on a thin film sensor element via a fluid. Then, the apparatus is configured as a respiratory synchronization signal generation device that receives a change in pressure detected by such a body motion detection sensor unit and generates a respiratory synchronization signal synchronized with respiration.

Thus, in order to achieve the above object, the invention according to claim 1 is provided on a bed on which a patient lies in a medical device such as a CT scan device, a PET device, a radiation treatment simulation device, and a radiation treatment device, A sensor unit that is inserted into a contact portion between a patient's back surface and a table to detect a change in pressure accompanying a breathing operation, and the sensor unit is stored in the hollow container having flexibility and the container. Formed from a thin film sensor element made of PVDF, aluminum nitride, or zinc oxide, and a fluid hermetically or liquid-tightly sealed in the container, and formed into a flat sheet shape as a whole. The acting pressure is configured to be detected by acting on the thin film sensor element via the fluid.
According to a second aspect of the present invention, in the sensor unit according to the first aspect, in the container, the area of the pressure receiving portion inserted into the contact portion between the back surface of the patient and the table is larger than the area of the thin film sensor element. It is comprised so that it may become.
According to a third aspect of the present invention, in a medical device such as a CT scan device, a PET device, a radiation treatment simulation device, or a radiation treatment device, the device is provided on a bed on which the patient lies, and the back surface of the patient is in contact with the table. A sensor unit that is inserted into a part to detect a change in pressure associated with a breathing operation, the sensor unit having a hollow first container that is flexible and has a flat sheet shape, and a hollow The second container, the pipes connecting the first and second containers and communicating the hollow portions thereof, and PVDF, aluminum nitride, or zinc oxide stored in the second container. A thin film sensor element, and fluids hermetically or liquid-tightly sealed in the first and second containers and the conduit, and pressure acting on the first container is mediated by the fluid. Configured to be detected acting on the thin film sensor element Te.
The invention according to claim 4 is the sensor unit according to any one of claims 1 to 3, wherein the fluid is a liquid made of silicon oil or mineral oil. According to the present invention, in the sensor unit according to any one of claims 1 to 3, the fluid is configured to be a gas composed of air or an inert gas.
According to a sixth aspect of the present invention, a change in pressure detected by the body motion detection sensor unit according to any one of the first to fifth aspects is received, and a respiratory synchronization signal synchronized with respiration is generated. In the apparatus according to claim 7, the body motion detection sensor unit is provided with a transmitter for the respiratory synchronization signal. The signal generating device is provided with a receiver corresponding to the transmitter, and is configured to transmit and receive the pressure change signal by Bluetooth communication or near infrared communication.
According to an eighth aspect of the present invention, in the respiratory synchronization signal generation device according to the sixth or seventh aspect, a video output terminal to which a monitor is connected is provided, and the respiratory waveform and the respiratory synchronization signal are graphed. Can be output.

As described above, according to the present invention, the body motion detection sensor unit includes a flexible hollow container, a thin film sensor element made of PVDF, aluminum nitride, or zinc oxide stored in the container, and a container. It is formed so as to form a flat sheet from the fluid hermetically or liquid tightly sealed, and the pressure acting on the container is detected by acting on the thin film sensor element via the fluid. Therefore, the pressure can be reliably detected via the fluid, and the breathing motion can be detected without requiring skill. The thin film sensor element is not subjected to direct force but pressure is applied via the fluid, so that the thin film sensor element does not deteriorate at an early stage, and the signal line connected to the thin film sensor element is not affected. Since no direct load is applied, the signal line is not disconnected and high durability is obtained. The body motion detection sensor unit is provided on a bed on which the patient lies, and is configured as a sensor unit that is inserted into a contact portion between the back surface of the patient and the table and detects a change in pressure accompanying a breathing operation. Therefore, the sensor unit does not collide with the tomography apparatus and does not hinder radiotherapy. Furthermore, since a thin film sensor element made of PVDF, aluminum nitride, or zinc oxide hardly absorbs X-rays, there is almost no risk of being reflected in a tomographic image. According to the present invention, the container of the body motion detection sensor unit is configured to be inserted into the contact portion of the back surface of the patient and the table so that the area of the pressure receiving portion is larger than the area of the thin film sensor element. It becomes possible to reliably detect a change in pressure. And according to the other structure of this invention, since a body movement detection sensor unit is comprised from the fluid enclosed with the hollow 1st container, the hollow 2nd container, the thin film sensor element, and the container. If the first container is laid on the patient's back, the first container does not absorb X-rays, so the sensor does not appear in the tomographic image and a clear tomographic image can be obtained. . Further, since the thin film sensor element is stored in a second container that is a container different from the first container that directly receives pressure, the thin film sensor element does not bend or deteriorate. Furthermore, there is no possibility that the signal line connected to the thin film sensor element is disconnected from the thin film sensor element. That is, the durability is very high. Furthermore, according to the present invention, since the fluid sealed in such a container is also configured to be a gas composed of air or an inert gas, even if the container is broken, liquid leakage, etc. Thus, the safety of expensive medical equipment can be ensured. In addition, according to the invention relating to the respiratory synchronization signal generation device that receives the signal from the body motion detection sensor unit by Bluetooth communication or near infrared communication and generates a respiratory synchronization signal, the sensor and the respiratory synchronization signal Since the generation device does not cause a malfunction of the medical device and the signal line does not get in the way, it is possible to safely install the signal generation device for respiratory synchronization. According to still another invention, the respiratory synchronization signal generation device is provided with a video output terminal so that the respiratory waveform and the respiratory synchronization signal can be graphed and output, so if a monitor is installed in the operator room, An operator who operates a device such as a tomography apparatus or a radiotherapy apparatus can confirm the breathing of the patient.

1 is a perspective view schematically showing a respiratory synchronization signal generation device and a CT scanning device according to an embodiment of the present invention. It is a perspective view showing typically a body movement detection sensor unit concerning an embodiment of the invention. It is a perspective view which shows typically the flexible IC chip which is a chip | tip for a connection which connects a thin film sensor element and a flat cable. It is sectional drawing which shows a mode that the thin film sensor element and the flat cable are connected by the flexible IC chip. It is a screen displayed on the monitor connected to the video output terminal of the signal generation apparatus for respiratory synchronization which concerns on embodiment of this invention. It is a perspective view which shows typically the body movement detection sensor unit which concerns on other embodiment of this invention.

The respiratory synchronization signal generation apparatus according to the present embodiment will be described using a CT scan apparatus provided with the respiratory synchronization signal generation apparatus as an example.
As shown in FIG. 1, the CT scanning apparatus 1 is generally configured by a gantry 2 that scans a human body, a bed 3 on which a patient lies, and the like, in the same manner as a conventionally known CT scanning apparatus. The gantry 2 has a through hole having a predetermined inner diameter into which a human body is inserted at the center thereof. That is, the opening 5 is provided. Although not shown in FIG. 1, the gantry 2 includes an X-ray source that emits X-rays and a detector array that includes a number of sensors that detect X-rays transmitted through the human body. 5 are provided at positions facing each other. Such an X-ray source and the detector array can be rotated in the circumferential direction around the opening 5 while adopting positions facing each other with the opening 5 interposed therebetween. The gantry 2 is provided with a computer that controls the gantry 2 and the bed 3 and processes data.

The bed 3 includes a pedestal 7 installed on the floor and a table 8 having a substantially rectangular plate shape provided on the pedestal 7. Although not shown in FIG. 1, the table 8 can be slid in the longitudinal direction by a table driving mechanism provided inside the pedestal 7. Such a bed 3 is installed adjacent to the gantry 2, and when the table driving mechanism is driven, the table 8 is inserted into the opening 5 or retracted.

The body motion detection sensor unit 11 according to the present embodiment is provided on the upper surface of the table 8. As will be described in detail later, the body movement detection sensor unit 11 is a sensor in which a pressure receiving portion that receives pressure is formed in a sheet shape, and when the patient lies on the upper surface of the table 8, , The body movement due to the movement of breathing can be detected as a change in voltage. A flat cable 12 is connected to the body motion detection sensor unit 11, and a transmitter 14 is connected to the tip of the flat cable 12. The transmitter 14 is fixed to the end surface of the long side of the table 8, and the flat cable 12 is sufficiently short. Therefore, the flat cable 12 and the transmitter 14 may interfere with tomographic image capturing or disturb the patient. There is no.

In the vicinity of the gantry 2, a respiratory synchronization signal generation device 16 is installed, and the respiratory synchronization signal generation device 16 and the gantry 2 are connected by a predetermined signal cable 18. The respiratory synchronization signal generation device 16 includes an open collector terminal, a TTL level line driver output terminal, a START / STOP output terminal, and an RS422 connection terminal, so that the signal cable 18 corresponds to the input terminal 19 of the gantry 2. Any type of cable can be selected. The respiratory synchronization signal generation device 16 is provided with a receiver or a receiver so that a signal transmitted from the transmitter 14 can be received. Note that the communication between the transmitter 14 and the receiver is performed by Bluetooth communication or near-infrared communication that does not cause malfunction of the device due to electromagnetic wave leakage. Therefore, the tomographic image apparatus 1 and medical devices installed in the vicinity are free from malfunction. Such a respiratory class signal generation device 16 is also provided with a video output terminal that can output necessary information to an external monitor device. Although not shown in FIG. Is connected to a predetermined monitor provided in the operator room. The breathing class signal generator 16 also includes a microphone. In general, the CT scanning device 1 emits a predetermined warning sound to call attention at the time of X-ray exposure. This warning sound can be detected and taken into the respiratory class signal generation device 16 as exposure information.

As shown in FIG. 2, the body motion detection sensor unit 11 according to the present embodiment includes a hollow first container 21 having a sheet shape with a large upper surface area, and a hollow second container having a predetermined size. And the thin film sensor element 23 stored in the second container 22. Since the first container 21 is a pressure receiving portion that is inserted between the patient's back surface and the table and receives the pressure on the patient's back surface, the first container 21 is formed of a flexible material such as polyvinyl chloride or polypropylene. The second container 22 is a container that protects the thin film sensor element 23, and therefore does not have to be particularly flexible. In the present embodiment, the second container 22 is formed from an acrylic resin. The first and

second containers

21 and 22 are connected in a gas-tight or liquid-tight manner by a connecting pipe 25 made of a flexible material, and the respective hollow portions communicate with each other. The thin film sensor element 23 is a thin film piezoelectric element having a predetermined size made of PVDF (polyvinylidene fluorite), aluminum nitride, or zinc oxide. In the present embodiment, the thin film sensor element 23 is made of aluminum nitride. The flat cable 12 is connected to the thin film sensor element 23 via a predetermined connection chip as described below, and the transmitter 14 is connected to the flat cable 12 as described above. The body motion detection sensor unit 11, that is, the first and

second containers

21 and 22 and the connecting pipe 25 are filled with silicon oil 27 and the thin film sensor element 23 is entirely immersed in the silicon oil 27. It has become.

The thin film sensor element 23 made of an aluminum nitride piezoelectric element and the flat cable 12 are connected by a predetermined connecting chip, that is, a flexible IC chip 30. As shown in FIG. 3, the flexible IC chip 30 is a flat chip with a cut 31, and first and second

conductive wires

33 and 34 made of a copper thin film are divided by the cut 31. The first small piece 35 and the second small piece 36 of the chip are provided so as to be parallel to each other. The first conducting wire 33 is provided on the front surface of the chip, and the second conducting wire 34 is provided on the back surface of the chip. A method of connecting the thin film sensor element 23 to the flat cable 12 using such a flexible IC chip 30 will be described. The thin film sensor element 23 is inserted into the cut 31 by bending the flexible IC chip 30 with the first small piece 35 downward and the second small piece 36 upward. Then, as shown in FIG. 4, the thin film sensor element 23 can be sandwiched between the first and second

small pieces

35 and 36 of the flexible IC chip 30. The thin film sensor element 23 has a structure in which a substrate 38 made of polyimide resin and an aluminum nitride crystal layer 39 deposited thereon are covered on the upper and lower surfaces by first and

second metal films

41 and 42 made of aluminum or the like. Presents. The anisotropic

conductive adhesives

44 and 44 are applied to the first and

second metal films

41 and 42 of the thin film sensor element 23 to press the first and second

small pieces

35 and 36 of the flexible IC chip 30. And glue. Then, the first metal film 41 and the first conductive wire 33, and the second metal film 42 and the second conductive wire 34 are electrically connected. A predetermined connector 47 is connected to the end 46 of the flexible IC chip 30, and the flat cable 12 is connected via the connector 47. The thin film sensor element 23 and the flat cable 12 are connected.

The operation of the CT scan apparatus 1 including the respiratory synchronization signal generation apparatus according to the present embodiment will be described. As shown in FIG. 1, the patient K is supine on the table 8 of the bed 3. At this time, the pressure receiving portion of the body motion detection sensor unit 11, that is, the position of the first container 21 is adjusted, and the pressure receiving portion hits a portion where the back surface of the patient and the table 8 are in contact, for example, near the shoulder rib or the hip. Insert like so. Patient K moves slightly due to breathing and heart movement. The pressure receiving portion of the body motion detection sensor unit 11 receives a change in pressure due to body motion. Then, the change in pressure applied via the silicon oil 27 is detected as a change in voltage in the thin film sensor element 23. Since the area of the pressure receiving portion is sufficiently large, it can receive the pressure of the back efficiently, and the pressure is uniformly applied to the entire surface of the thin film sensor element 23 by the silicon oil 27, so that the change in pressure can be detected with high accuracy. it can. The detected voltage change is transmitted to the respiratory synchronization signal generation device 16 by the transmitter 14. The respiratory synchronization signal generator 16 processes a waveform of the input voltage to generate a pulse signal synchronized with respiration, that is, a synchronization signal. The generated synchronization signal is input to the gantry 2. By the way, the voltage waveform includes different frequency components due to breathing motion and heartbeat, and further includes noise. Accordingly, a known analysis method such as Fourier transform or wavelet transform is applied to extract a frequency component corresponding to the breathing motion. Then, the timing of breathing can be obtained. Since the input power waveform contains many frequency components that change in a short time, an analysis method using wavelet transform is particularly effective. As an analysis method, for example, the Japan Society of Mechanical Engineers [No. 01-5] Dissertation Symposium CD-ROM [2001.8.7, Tokyo] paper "W301 Study on unrestrained invasive measurement of respiratory and heart rate during sleep using PVDF sensor (2nd report: Wavelet transform The method described in “Detection of respiratory heartbeat used)” can be applied.

The table 8 is driven to insert the patient K into the opening 5 so that the site where the tomographic image is to be taken is positioned at the center of the opening 5. In synchronism with the synchronizing signal input to the gantry 2, the X-rays are exposed to take a tomographic image. At this time, the pressure receiving part inserted in the contact part between the back surface of the patient K and the table, that is, the first container 21 of the body motion detection sensor unit 11 and the silicon oil 27 do not absorb X-rays. These are not reflected in. Subsequently, the table 8 is driven to slightly insert the patient K, and a tomographic image is taken in synchronization with the synchronization signal. Thereafter, a plurality of tomographic images are taken in the same manner.

On the monitor provided in the operator room, the screen output from the respiratory synchronization signal generator 16 is displayed, for example, as shown in FIG. The screen 51 displays basic information such as the date and time 52, the patient ID 53 given to the patient K, the patient's name 54, and the like, along with the display of the respiratory waveform 56 of the patient K and the respiration synchronized with the respiratory waveform 56 The synchronizing signal 57 is displayed in a pulse shape. Further, the timing at which the CT scanning device 1 is exposed, that is, the exposure information 59 and the heartbeat signal 60 are also displayed. The operator can monitor the breathing state while observing the display on the monitor, and give an instruction to the patient K through a voice line provided in the operator room. Then, the patient K can perform an appropriate breathing motion and can appropriately capture a tomographic image. Note that a predetermined memory is also provided in the respiratory synchronization signal generation device 16, and information displayed on the monitor is stored. Therefore, past data can also be displayed as necessary.

FIG. 6 shows a body motion detection sensor unit 11 ′ according to the second embodiment. Elements similar to those of the body motion detection sensor unit 11 according to the above-described embodiment are assigned the same reference numerals and will not be described in detail. As shown in FIG. 5, the body motion detection sensor unit 11 ′ according to the second embodiment includes a thin film sensor element 23 stored in a first container 21 ′, and the second container Not provided. That is, the thin film sensor element 23 is stored in a predetermined portion of the first container 21 ′ that is a pressure receiving portion. If it does in this way, it will become possible to manufacture body motion detection sensor unit 11 'more cheaply. In addition, if the predetermined reinforcement member is provided about the part in which the thin film sensor element 23 of the first container 21 ′ is stored, the thin film sensor element 23 can be appropriately protected.

The tomographic image apparatus according to the present embodiment can be variously modified. For example, the body motion detection sensor unit 11 and the respiratory synchronization signal generation device 16 are described as being wirelessly communicated by a transceiver, but may be directly connected by a predetermined signal cable. However, such a signal cable needs to be wired on the backside or edge of the table of the bed so as not to interfere with tomographic image capturing. Further, the first and

second containers

21 and 22 of the body motion detection sensor unit 11 are described as being filled with silicon oil, but the same applies to other liquids such as mineral oil. be able to. Furthermore, instead of such a liquid such as silicon oil, an inert gas such as carbon dioxide or nitrogen gas, or a gas such as air may be enclosed. Then, even if the first and

second containers

21 and 22 are damaged, a liquid leakage accident does not occur.

DESCRIPTION OF SYMBOLS 1 CT scan apparatus 2 Gantry 3 Bed 5 Opening part 7 Base 8 Table 11 Body motion detection sensor unit 12 Flat cable 14 Transmitter 16 Breathing synchronization signal generation apparatus 21 First container 22 Second container 23 Thin film sensor element 25 Connection Tube 27 Silicon oil 51 Screen

Claims

In a medical device such as a CT scan device, a PET device, a radiation treatment simulation device, a radiation treatment device, etc., a pressure that is provided on a bed on which the patient lies and is inserted into a contact portion between the patient's back and the table and is associated with a breathing operation. A sensor unit for detecting a change in
The sensor unit includes a flexible hollow container, a thin film sensor element made of PVDF, aluminum nitride, or zinc oxide stored in the container, and hermetically or liquid-tightly sealed in the container. Formed from a fluid to form a flat sheet,
A body motion detection sensor unit, wherein pressure acting on the container is detected by acting on the thin film sensor element via the fluid.
The sensor unit according to claim 1, wherein the container has an area of a pressure receiving portion inserted into a contact portion between the back surface of the patient and the table, which is larger than an area of the thin film sensor element. Motion detection sensor unit.
In a medical device such as a CT scan device, a PET device, a radiation treatment simulation device, a radiation treatment device, etc., a pressure that is provided on a bed on which the patient lies and is inserted into a contact portion between the patient's back and the table and is associated with a breathing operation. A sensor unit for detecting a change in
The sensor unit is connected to the hollow first container, the hollow second container, and the first and second containers, which are flexible and have a flat sheet shape as a whole. A conduit communicating with the hollow portion; a thin film sensor element made of PVDF, aluminum nitride, or zinc oxide stored in the second container; and the first and second containers and the conduit are airtight or liquid Consisting of a tightly sealed fluid,
A body motion detection sensor unit, wherein a pressure acting on the first container acts on the thin film sensor element via the fluid and is detected.
The sensor unit according to any one of claims 1 to 3, wherein the fluid is a liquid made of silicon oil or mineral oil.
The sensor unit according to any one of claims 1 to 3, wherein the fluid is a gas composed of air or an inert gas.
A respiratory synchronization signal that receives a change in pressure detected by the body motion detection sensor unit according to any one of claims 1 to 5 and generates a respiratory synchronization signal synchronized with respiration. Signal generator.
The apparatus according to claim 6, wherein the body motion detection sensor unit is provided with a transmitter, and the respiratory synchronization signal generation apparatus is provided with a receiver corresponding to the transmitter, and the pressure change signal is received by the transmitter. , Bluetooth communication, or near-infrared communication is used for transmission / reception.
The respiratory synchronization signal generation device according to claim 6 or 7 is provided with a video output terminal to which a monitor is connected, and can output a respiratory waveform and a respiratory synchronization signal in a graph. A signal generator for respiratory synchronization.