JP5042542B2 - Capsule medical device and capsule medical device system - Google Patents

Abstract

Smooth guiding through the inside of a body cavity is carried out by a magnetic field applied from the outside of the body. The provided capsule medical device (1) includes a bio-information detecting device (5) for detecting bio information of the inside of a body cavity; a magnet (12) for receiving a guidance magnetic field applied from outside the body and generating a driving force; a coil (7) for receiving a position-detection magnetic field applied from outside the body and generating a position-detection signal; a filter device (8), connected to the coil (7), for attenuating an induction signal component which is generated by the guidance magnetic field incident on the coil (7); and a wireless transmission device (10) for externally transmitting the position-detection signal which has passed through the filter device (8) and the bio information which has been detected by the bio-information detecting device (5).

Description

  The present invention relates to a capsule medical device and a capsule medical device system that are inserted into a body cavity.

A capsule medical device system is known in which a magnet is provided in a capsule medical device and a magnetic field is applied from outside to control the position and posture of the capsule medical device (see, for example, Patent Document 1).
In the capsule medical device system of Patent Document 1, a helical thrust generating mechanism is provided on the outer peripheral surface of the capsule endoscope, and the capsule medical device is propelled by applying a rotating magnetic field to an internal magnet from outside the body. ing.

Further, in this capsule medical device system, a magnetic field for position detection is generated from outside the body, and an induced magnetic field generated in a magnetic induction coil disposed in the capsule medical device is detected outside the body, thereby enabling capsule medical treatment in a body cavity. The current position and orientation of the device are to be detected. Thereby, the capsule medical device can be smoothly guided in the body cavity.
JP 2005-245963 A

  However, in such a capsule medical device system, since the capsule is guided and the capsule position is detected by applying a magnetic field from outside the body, the magnetic induction coil in the capsule medical device is used for position detection. In addition to the magnetic field, the rotating magnetic field for guiding the capsule medical device may also act, and the accurate position and orientation of the capsule medical device may not be detected. In this case, there is a problem that the capsule medical device cannot be smoothly guided.

  In addition, when the capsule medical device is propelled while being rotated by the rotating magnetic field applied from outside the body and the helical thrust generating mechanism provided on the outer peripheral surface of the capsule medical device, the friction between the capsule medical device and the surrounding organs For example, rotation may not be performed smoothly, and the direction of the magnetic pole of the magnet in the capsule medical device may not match the direction of the rotating magnetic field. Even in this case, there is a problem that the capsule medical device cannot be smoothly guided.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a capsule medical device and a capsule medical device system that can be smoothly guided in a body cavity by a magnetic field applied from outside the body. Yes.

In order to achieve the above object, the present invention provides the following means.
The present invention is directed to a living body information detecting device for detecting living body information in a body cavity, a guidance magnetic field acting from outside the body, receiving a magnet for generating a driving force, and a position detecting magnetic field acting from outside the body. A coil that generates a signal, a filter device that is connected to the coil and attenuates an induction signal component caused by the magnetic field for guidance incident on the coil, and the induction signal and biological information detection device that have passed through the filter device Provided is a capsule medical device including a wireless transmission device that transmits detected biological information to the outside.

  According to the present invention, when a guidance magnetic field acts from outside the body, a driving force is generated by an internal magnet, and the capsule medical device in the body cavity is promoted. Further, when a position detection magnetic field acts from outside the body, an induction signal is generated by an internal coil, and therefore the position and orientation of the capsule medical device can be detected based on the induction signal. Then, the desired biological information in the body cavity can be detected by detecting the correct position and orientation and operating the biological information detecting device in a state guided to the desired position and posture.

  In this case, both the guidance magnetic field and the position detection magnetic field from outside the body act on the internal coil, and an induction signal is generated by the magnetic induction, but the filter device is connected to the coil. Among the induced signals, the induced signal due to the guidance magnetic field is attenuated. And the guidance signal by the remaining magnetic field for position detection in which the guidance signal by the magnetic field for guidance was attenuate | damped is transmitted outside with the action | operation of a radio | wireless transmitter with the detected biometric information. Therefore, it is possible to receive a guidance signal that is less influenced by the guidance magnetic field outside the capsule medical device, and it is possible to improve the position and orientation detection accuracy and perform smooth guidance.

In the said invention, it is preferable that the opening direction of the said coil and the direction of the magnetic field formed by the said magnet in the position of this coil are substantially orthogonal.
By doing so, the magnetic field formed by the magnet is prevented from passing through the coil, the influence of the magnet on the induction signal is reduced, the position and orientation detection accuracy is improved, and smooth guidance is performed. be able to.

Moreover, in the said invention, it is good also as two or more said coils being provided and the opening direction of each coil differing.
In this way, two or more induction signals can be obtained according to one magnetic field acting from outside the body, and the six degrees of freedom necessary to determine the six degrees of freedom of the capsule medical device by three or more different magnetic fields. The above induction signal can be obtained.

Moreover, in the said invention, it is good also as said coil being arrange | positioned in the same position.
By doing in this way, the accommodation space of a coil can be reduced and a capsule medical device can be reduced in size.

Moreover, in the said invention, the identification information required in order to detect a position and a direction with the said guidance signal is hold | maintained, and the said radio | wireless transmitter is good also as transmitting identification information outside.
By doing in this way, based on the identification information and the guidance signal transmitted to the outside via the wireless transmission device, it is possible to easily detect the position and direction of different types of capsule medical devices.

In the above invention, two or more coils may be provided, and the identification information may include a relative position of the coils and a relative angle in the opening direction.
In the above invention, two or more coils are provided, and the identification information includes a relative position and a relative angle of the coil, a relative position between the coil and the magnet, an opening direction of the coil, and a magnetization direction of the magnet. It is good also as including the relative angle with.
In this way, the position and direction of the capsule medical device based on the relative position of the two or more coils, the relative angle in the opening direction and / or the relative angle between the opening direction of the coil and the magnetization direction of the magnet and the induction signal. Can be easily detected.

Moreover, in the said invention, it is good also as providing the switching apparatus which switches the connection of the said 2 or more coil and the said filter apparatus.
By doing so, the number of filter devices can be reduced, and the capsule medical device can be reduced in size and weight.

In the above invention, the guidance signal processing device that processes the guidance signal that has passed through the filter device and inputs the guidance signal to a wireless transmission device is provided, and the guidance signal processing device and the biological information detection device are synchronized with each other. It may be operated.
In this way, in synchronization with the detection of the biological information by the biological information detection device, the processing of the position detection induction signal by the induction signal processing device is stopped except when the position detection magnetic field acts from the outside. This can save power.
In the above invention, the switching device and the biological information detection device may be operated in synchronization.

  The present invention also includes any one of the capsule medical devices described above and an external device disposed outside the body, and the external device receives a signal transmitted from the wireless transmission device, A guidance signal extraction device that extracts the guidance signal from a signal received by a wireless reception device, and a position / direction calculation device that calculates the position or orientation of the capsule medical device based on the guidance signal extracted by the guidance signal extraction device A capsule medical device system comprising: a guidance magnetic field generation device that generates the guidance magnetic field; and a position detection magnetic field generation device that generates the position detection magnetic field.

  According to the present invention, when the guidance magnetic field is generated from outside the body by the operation of the guidance magnetic field generator provided in the external device, the driving force is generated by the magnet inside the capsule medical device, and the capsule medical device in the body cavity is Promoted. And the biological information in a body cavity is detected by the action | operation of the biological information detection apparatus in a capsule medical device.

  In addition, when a position detection magnetic field acts from outside the body due to the operation of the position detection magnetic field generation device provided in the external device, an induction signal is generated by a coil inside the capsule medical device. The generated induction signal is transmitted to the outside of the body together with the biological information by the operation of the wireless transmission device after the filter device attenuates the induction signal component generated by the action of the guidance magnetic field.

  The guidance signal transmitted to the outside of the body is received by the wireless reception device provided in the external device, separated and extracted from the biological information by the guidance signal extraction device, and then the position of the capsule medical device or Used to calculate the orientation. Due to the operation of the filter device, the guidance signal component due to the guidance magnetic field is attenuated from the guidance signal used to calculate the position or orientation, so the capsule medical device can be guided smoothly by accurately calculating the position and orientation. can do. The desired biological information in the body cavity can be detected by the capsule medical device guided to the desired position and posture.

  The present invention also includes any one of the capsule medical devices described above and an external device disposed outside the body, and the external device receives a signal transmitted from the wireless transmission device, An information extraction device for extracting the guidance signal and the identification information from the signal received by the wireless reception device, and the position, orientation and magnet of the capsule medical device based on the guidance signal and the identification information extracted by the information extraction device Provided is a capsule medical device system comprising a position direction calculation device for calculating the magnetization direction, a guidance magnetic field generation device for generating the guidance magnetic field, and a position detection magnetic field generation device for generating the position detection magnetic field. .

  According to the present invention, the identification information held in the identification information holding device of the capsule medical device is received by the external device via the wireless transmission device of the capsule medical device and the wireless reception device of the external device. In the external device, the position and orientation of the capsule medical device and the magnetization direction of the magnet are accurately calculated by the operation of the position / direction calculation device based on the guidance signal and identification information extracted by the information extraction device. Thereby, even if the capsule medical device to be used is changed, the capsule medical device can be guided more smoothly.

  The present invention also includes the capsule medical device and an external device arranged outside the body, wherein the external device receives a signal transmitted from the wireless transmission device, and the wireless reception device. An information extraction device for extracting the guidance signal from the signal received by the device, an identification information holding device for holding identification information including a relative position of two or more coils of the capsule medical device and a relative angle in the opening direction, and the identification A position / direction calculating device for calculating the position and orientation of the capsule medical device and the magnetization direction of the magnet based on the identification information read from the information holding device and the guidance signal extracted by the information extracting device; and the guidance magnetic field Providing a capsule medical device system comprising: a guidance magnetic field generator for generating a position detection; and a position detection magnetic field generator for generating the position detection magnetic field. To.

  According to the present invention, based on the identification information held in the identification information holding device provided in the external device and the guidance signal transmitted from the capsule medical device, the capsule medical device is operated by the operation of the position / direction calculating device. The position, orientation, and magnetization direction of the magnet are accurately calculated. Thereby, the capsule medical device can be guided more smoothly by registering the identification information of the capsule medical device to be used.

In the above invention, the guidance magnetic field generating device may be controlled based on the position and orientation of the capsule medical device calculated by the position / direction calculating device and the magnetization direction of the magnet.
By doing so, it becomes possible to generate an optimum guidance magnetic field based on the position and orientation of the capsule medical device and the magnetization direction of the magnet, and the capsule medical device can be guided more smoothly.

  According to the present invention, there is an effect that it can be smoothly guided in a body cavity by a magnetic field applied from outside the body.

A capsule medical device 1 and a capsule medical device system 2 according to an embodiment of the present invention will be described below with reference to FIGS.
As shown in FIG. 1 and FIG. 2, the capsule medical device system 2 according to the present embodiment is disposed outside the body of the subject and the capsule medical device 1 that is put into the body cavity of the subject (not shown). The external device 3 is provided.

As shown in FIGS. 3 and 4, the capsule medical device 1 includes an exterior 4 that houses various devices therein, and an imaging unit that captures images (biological information) by imaging the body cavity of the subject. (Biological information detection device) 5, a power supply unit 6 that supplies power to various devices in the exterior 4, and a magnetic field sensor coil that generates an induction signal in accordance with magnetic fields M ₁ and M ₂ received from the external device 3 7, a filter 8 that filters the induction signal generated by the coil 7, an induction signal processing unit 9 that processes the induction signal that has passed through the filter 8, and directs the processed induction signal outside the body. Is transmitted according to the magnetic fields M ₁ and M ₂ received from the external device 3 and the control unit 11 that controls the power supply unit 6, the imaging unit 5, the induction signal processing unit 9, and the wireless transmitter 10. Permanent magnet (magnet) that generates force And a 2.

The exterior 4 includes a cylindrical capsule body 4a that transmits infrared rays with the longitudinal axis R of the capsule medical device 1 as a central axis, a transparent hemispherical tip 4b that covers the front end of the capsule body 4a, and a capsule body The capsule container is formed from a hemispherical rear end portion 4c covering the rear end of 4a and sealed with a watertight structure.
The outer peripheral surface of the capsule body 4a of the outer package 4 is provided with a spiral portion 13 in which a wire having a circular cross section around the longitudinal axis R is spirally wound.

  The imaging unit 5 forms on the image sensor 15 an image of the image sensor 15 disposed on the surface on the distal end portion 4b side of the substrate 14a disposed substantially perpendicular to the longitudinal axis R, and an image of the body cavity inner surface of the subject. A lens group 16 to be illuminated, and an LED (Light Emitting Diode) 17 that illuminates the inner surface of the body cavity.

The image sensor 15 converts the light imaged through the distal end portion 4 b and the lens group 16 into an electrical signal (image signal) and outputs it to the control unit 11. For example, a CMOS (Complementary Metal Oxide Semiconductor) or a CCD can be used as the image sensor 15.
In addition, a plurality of LEDs 17 are arranged on the support member 18 arranged at the distal end portion 4b from the substrate 14a with an interval in the circumferential direction about the longitudinal axis R.
The filter 8 is provided on the substrate 14a, for example, and is, for example, a primary high-pass filter having a cutoff frequency of about 1 kHz.

  The induction signal processing unit 9 controls an A / D converter (indicated as ADC in the figure) 19 that converts the induction signal that has passed through the filter 8 into a digital signal, and the A / D converter 19. An A / D converter control unit (indicated with an ADC control unit in the figure) that delivers the induction signal output from the A / D converter 19 and the image signal acquired by the image sensor 15 to the wireless transmitter 10 at a predetermined timing. 20).

  More specifically, the A / D converter control unit 20 is connected to the control unit 11 and input to the clock signal Clock received from the control unit 11 and the control unit 11 as shown in FIG. A timing generation circuit 21 that generates a timing signal based on a synchronization signal (for example, a vertical synchronization signal V-Sync) obtained from an image signal, and a memory 22 that stores a digital induction signal output from the A / D converter 19 And a multiplexer connected to the memory 22, the timing generation circuit 21, and the control unit 11, and switching and outputting the image signal from the control unit 11 and the induction signal from the memory 22 by the timing signal from the timing generation circuit 21. 23. The timing generation circuit 21 outputs a clock signal AD Clock and an A / D conversion enable signal to the A / D converter 19.

  The control unit 11 is electrically connected to the battery 25 via the substrates 14a to 14d and the flexible substrates 24a and 24b, and is electrically connected to the image sensor 15 via the substrate 14a. The LED 17 is electrically connected to the LED 17 through the support 24a and the support member 18. The control unit 11 outputs the image signal acquired by the image sensor 15 to the A / D converter control unit 20 and controls on / off of the image sensor 15 and the LED 17.

In addition, the control unit 11 controls the wireless transmitter 10 to transmit the signal output from the multiplexer 23 of the A / D converter control unit 20 to the outside.
That is, for example, the wireless transmitter 10 is configured to transmit the image signal having a predetermined length and the induction signal to the outside in the form of a continuous data.

  The permanent magnet 12 is disposed on the rear end 4 c side of the wireless transmitter 10. The permanent magnet 12 is arranged or magnetized so as to have a magnetization direction (magnetic pole) in a direction orthogonal to the longitudinal axis R (for example, the vertical direction in the figure). On the tip portion 4b side of the permanent magnet 12, a switch portion 26 disposed on the substrate 14c is provided. The switch unit 26 includes an infrared sensor 26a, and is electrically connected to the power supply unit 6 and is also electrically connected to the battery 25 via the substrate 14c and the flexible substrate 24a.

A plurality of switch portions 26 are arranged at equal intervals in the circumferential direction around the longitudinal axis R, and the infrared sensor 26a is arranged so as to face the outside in the diameter direction. In the present embodiment, an example in which four switch units 26 are arranged will be described, but the number of switch units 26 is not limited to four, and any number may be used.
On the distal end 4b side of the switch portion 26, the battery 25 is disposed between the substrates 14b and 14c.

The coil 7 is disposed so as to be wound in a cylindrical shape inward in the radial direction of the capsule body 4 a of the exterior 4. In the figure, reference numeral 27 denotes a core member (magnetic core) made of ferrite formed in a cylindrical shape whose central axis substantially coincides with the longitudinal axis R.
Thereby, the opening direction of the coil 7 is arranged in a direction orthogonal to the magnetization direction of the permanent magnet 12. As a result, the magnetic field formed by the permanent magnet 12 is prevented from passing through the inside of the coil 7, and the induction signal generated in the coil 7 is not affected by the magnetic field formed by the permanent magnet 12.

As shown in FIGS. 2 and 6, the external device 3 receives a signal sent from the capsule medical device 1 and generates a magnetic field M ₂ for position detection, and the external device 28. The external control unit 29 that generates an image based on the signal received by the computer and calculates the position and orientation of the capsule medical device 1, and the position and orientation information of the capsule medical device 1 that is output from the external control unit 29 a guidance-magnetic-field generating unit 30 for generating a guidance magnetic field M ₁ on the basis, and a display device 31 for displaying an image based on the image signal outputted from the external control unit 29.

The extracorporeal device 28 includes a radio receiver 33 that receives an image signal and a guidance signal sent from the capsule medical device 1 via the antenna unit 32, and data separation that separates the received signal into an image signal and a guidance signal. Unit 34, an image data compression unit 35 for compressing the separated image signal, a data synthesis unit 36 for synthesizing the compressed image signal and the separated induction signal, and a memory 37 for storing the synthesized data And a position detecting magnetic field generating unit 38 for generating a position detecting magnetic field M ₂ based on the signal received by the wireless receiver 33.

The signal received by the wireless receiver 33 includes an image signal and an induction signal. Since the image signal has a predetermined length, the data separation unit 34 determines the image signal and the induced signal. Subsequent induction signals can be easily separated.
The position detection magnetic field generation unit 38 detects a trigger signal included in the image information, for example, a trigger detection unit 39 that detects the vertical synchronization signal V-Sync, and detects the position at a timing based on the detected trigger signal. includes a position detection signal generator 40 for outputting a signal, and a plurality of signal generating coils 41 for generating a magnetic field M ₂ for position detection based on the signal output by the position detection signal generator 40 Yes.

  The external control unit 29 expands the compressed image signal sent from the extracorporeal device 28 and outputs the compressed image signal to the display device 31, and the guidance signal sent from the extracorporeal device 28. Based on the position / direction calculation unit 43 that calculates the position and orientation of the capsule medical device 1 and outputs the calculated position and orientation to the display device 31, the image of the inner surface of the body cavity displayed on the display device 31 and the position and orientation of the capsule medical device 1. And an operation unit 44 for instructing the traveling direction and / or traveling speed of the capsule medical device 1.

The position direction calculation unit 43 processes the received induction signal, and from the induction signal, a specific frequency having a frequency substantially the same as the frequency of the position detection magnetic field M ₂ generated by the position detection magnetic field generation unit 40. A signal is extracted, and the position and orientation of the capsule medical device 1 are calculated based on the extracted specific frequency signal.

The guidance magnetic field generation unit 30 generates a control signal for the guidance magnetic field M ₁ based on the operation command signal output from the external control unit 29 and information such as the position and orientation of the capsule medical device 1. and the guidance-magnetic-field control unit 45 which, based on a control signal from the guidance-magnetic-field control unit 45, a plurality of guidance coils 46 that generates the guidance magnetic field M _1, the guidance coil for supplying current to these guidance coils 46 And a driver 47.

Here, the effect | action of the filter 8 mentioned above is demonstrated.
As the guidance magnetic field M1 generated in the guidance magnetic field generation unit 30, for example, a strong magnetic field of ₁ mT to 1T is used. In addition, in order to control the position and posture of the capsule medical device 1, the guidance magnetic field M ₁ is changed in its generation direction and magnetic field strength at a frequency of 100 Hz or less.
On the other hand, as the magnetic field M ₂ for position detection, a magnetic field having a magnetic field intensity of about 0.01 μT to 100 μT and a frequency of several kHz to several hundred kHz at the position of the capsule medical device 1 is used. .

If to be modified by the capsule medical apparatus guidance magnetic field M ₁ in the direction of 1, a magnetic torque by providing an angle between the magnetization direction and guidance magnetic field M ₁ direction of the capsule medical apparatus 1 inside the permanent magnet 12 Is generated. Magnetic torque, angle between the magnetization direction and guidance magnetic field M ₁ direction of the permanent magnet 12 is maximum when it becomes a 90 °.

The coil 7 in the capsule medical device 1 receives a magnetic field and generates an induction (voltage) signal. If this induction signal is V,
V = 2πfBSN cos θ
It becomes. Here, f is the frequency of the magnetic field, B is the strength of the magnetic field, S is the cross-sectional area of the coil, N is the number of turns of the coil 7, and θ is the angle between the magnetic field direction and the opening direction of the coil 7.

For example, the strength of the guidance magnetic field M ₁ is 100 mT, the frequency is 10 Hz, the strength of the position detection magnetic field M ₂ is 1 μT, the frequency is 10 kHz, the angle between the opening direction of the coil 7 and the direction of the magnetic field is 60 °, and the sectional area of the coil 7 is 10 ×. 10 ^-6 m ^2, as a number of turns 400 of the coil 7, when determining the induction signal V generated by the coil 7, the induction signal due to the guidance magnetic field _{M 1} strength of about 100 mV, the induction signal due to the position-detection magnetic field _{M 2} The intensity is about 2 mV.

The signals detected in this state are as shown in FIG.
Then, when it is A / D converts the signal, would spend the induction signal generated by the guidance magnetic field M ₁ most of the dynamic range of the A / D converter 19, the induction signal due to the position-detection magnetic field M ₂ It cannot be detected accurately.

In the present embodiment, by connecting the coil 7 with the high-pass filter 8 having a cutoff frequency of about 1 kHz, it is possible to attenuate the induction signal at the frequency 10 Hz of the guidance magnetic field M ₁ by −40 dB. Thus, as shown in FIG. 8 attenuates the induction signal generated by the guidance magnetic field M ₁ to about 1 mV, it is possible to transmit it remains approximately 2mV induction signal generated by the position-detection magnetic field M _2.
Thus, by connecting the filter 8 to the coil 7, by reducing the influence of the guidance magnetic field M _1, the induction signal generated by the position-detection magnetic field M ₂ can be detected accurately.

The operation of the capsule medical device 1 and the capsule medical device system 2 according to this embodiment configured as described above will be described below.
In order to acquire an image in the body cavity of the subject using the capsule medical device system 2 according to the present embodiment, first, the guidance magnetic field M ₁ by the guidance coil 46 arranged as shown in FIG. A subject is placed in the space S where it acts.

  Next, the capsule medical device 1 is turned on by applying infrared rays to the infrared sensor 26a of the capsule medical device 1 with an infrared generator (not shown). Then, the capsule medical device 1 is introduced into the body cavity from the mouth or anus of the subject. In the external device 3 as well, the power switch 48 of the extracorporeal device 28 is operated by the battery 49 to switch the power supply unit 50 to the ON state, thereby supplying power to each unit.

  In the capsule medical device 1 placed in the body cavity, the operation of the imaging unit 5 is started after a predetermined time, and the image of the inner surface of the body cavity illuminated by the illumination light from the LED 17 is acquired by the image sensor 15. The acquired image signal is sent to the A / D converter control unit 20 via the control unit 11 and set by the timing generation circuit 21 based on the clock signal Clock and the vertical synchronization signal V-Sync generated by the control unit 11. At this timing, it is delivered to the wireless transmitter 10 and transmitted to the outside of the body via the wireless transmitter 10.

The transmitted image signal is received by the wireless receiver 33 via the antenna unit 32 provided in the extracorporeal device 28. The received image signal is input to the position detection magnetic field generator 38, and a trigger signal such as the vertical synchronization signal V-Sync is detected. Then, based on the detected trigger signal, the position detection signal generator 40 is activated, are excited signal generating coil 41, a magnetic field M ₂ is a position detection space S are arranged subject generated To do.

When the generated position detection magnetic field M ₂ acts on the capsule medical device 1, the position detection magnetic field M ₂ passes through the coil 7 in the capsule medical device 1, whereby an induction signal is induced in the coil 7. The induction signal is input to the induction signal processing unit 9 via the filter 8, A / D converted according to the timing set by the timing generation circuit 21, and then stored in the memory 22. Then, it is handed over to the wireless transmitter 10 via a multiplexer (indicated as MUX in the figure) 23 that is switched at the timing set by the timing generation circuit 21, and transmitted outside the body via the wireless transmitter 10.

  The transmitted induction signal is received by the wireless receiver 33 via the antenna unit 32 provided in the extracorporeal device 28. The received induction signal is separated from the image signal by the data separation unit 34. The separated guidance signal is sent to the external control unit 29 as it is, and the image signal is compressed by the image data compression unit 35 and then sent to the external control unit 29. In addition, the induction signal and the compressed image signal are combined in a form corresponding to each other in the data combining unit 36 and stored in the memory 37.

The image signal sent to the external control unit 29 is decompressed by the image decompression processing unit 42, sent to the display device 31 and displayed. The guidance signal sent to the external control unit 29 is sent to the position / direction calculation unit 43 and used to calculate the position and orientation of the capsule medical device 1. The calculated position and orientation of the capsule medical device 1, while being displayed is sent to the display device 31, it is sent to the guidance-magnetic-field generating unit 30, used for calculating the guidance magnetic field M ₁ to be generated.

An operator who has confirmed the image of the inner surface of the body cavity displayed on the display device 31 and information on the position and orientation of the capsule medical device 1 operates the operation unit 44 of the external control unit 29, thereby The traveling speed is input to the guidance magnetic field generator 30. The guidance magnetic field generator 30 should be generated based on the direction and speed command signals input from the operation unit 44 and the position and orientation information of the capsule medical device 1 input from the position direction calculator 43. intensity and direction of the guidance magnetic field M ₁ operates the guidance coil driver 47 so as to achieve. Thus, the guidance coil 46 is energized, a magnetic field M ₁ is generated for a desired guidance in the space S which is present in the subject.

When the magnetic field for guidance M ₁ acts on the capsule medical device 1, the permanent magnet 12 disposed in the capsule medical device 1 causes the capsule medical device 1 to align with the direction of the magnetic field for guidance M _1. A driving force to rotate is generated. The magnetization direction of the guidance magnetic field M ₁ is a permanent magnet 12, to occur in a direction inclined to the longitudinal axis R of the capsule medical apparatus 1, the driving force is generated so that the orientation of the capsule medical device 1 is changed. On the other hand, when the driving force is generated inclining in the circumferential direction of the capsule medical device 1 with respect to the magnetization direction of the permanent magnet 12, the driving force is generated so that the capsule medical device 1 is rotated about the longitudinal axis R.

  Since the spiral mechanism 13 is provided on the outer peripheral surface of the exterior of the capsule medical device 1, when the capsule medical device 1 rotates around its longitudinal axis R by the driving force, the spiral mechanism 13 propels it along the longitudinal axis R direction. Force is generated. Thereby, the capsule medical device 1 is propelled in the longitudinal axis R direction.

In this case, both of the guidance magnetic field M ₁ and the position detection magnetic field M ₂ are incident on the coil 7 disposed in the capsule medical device 1, and each corresponds to the strength of the magnetic fields M ₁ and M _2. was it induced signal is generated, according to the capsule medical device 1 and the capsule medical device system 2 according to the present embodiment, since the filter 8 to the coil 7 is connected, the induction signal is attenuated by the guidance magnetic field M ₁ In this state, A / D conversion is performed and the data is transmitted to the external device 3. Therefore, in the external apparatus 3, as described above, it becomes possible to reduce the effect of the guidance magnetic field M _1, the induction signal generated by the position-detection magnetic field M ₂ can be detected accurately.

Therefore, since the position and orientation of the capsule medical device 1 are accurately calculated using the position detection guidance signal thus accurately detected, the guidance magnetic field control unit 45 is responsive to a command from the operator. so as to generate a magnetic field M ₁ for exact guidance depending, it can drive the guidance coil driver 47. As a result, there is an effect that the capsule medical device 1 can be guided with high accuracy and an image of a desired part in the body cavity can be acquired.

In the capsule medical device system 2 according to the present embodiment, the capsule medical device 1 and the external device 3 are operated in synchronization with each other based on the timing generated based on the vertical synchronization signal V-Sync extracted from the image signal. Therefore, only when the position detection magnetic field M ₂ is generated from the extracorporeal device 28, the capsule medical device 1 can A / D convert the induction signal from the coil 7. Therefore, it is possible to keep stop processing of the induced signals due to the induction signal processing unit 9 during the period when the position-detection magnetic field M ₂ is not generated, it is possible to save power.

In the present embodiment, the capsule medical device 1 and the external device 3 are synchronized by the timing generated based on the vertical synchronization signal V-Sync extracted from the image signal. However, the present invention is not limited to this. Instead, it may be synchronized with timing generated based on another trigger signal such as a horizontal synchronization signal extracted from the image signal.
In addition, a high-pass filter with a cutoff frequency of 1 kHz is employed as the filter, but a band-pass filter may be employed instead.

In the present embodiment, a helical mechanism 13 provided on the outer peripheral surface of the capsule medical apparatus 1, although a possible propelling rotating the capsule medical apparatus 1, utilizing the magnetic gradient by the magnetic field distribution changes in the guidance magnetic field M ₁ And it is good also as a structure which generates the force (thrust) in the permanent magnet 12, and controls the position of the capsule medical device 1 by this.

Next, a capsule medical device 1 ′ and a capsule medical device system according to a second embodiment of the present invention will be described with reference to FIGS. 9 and 10.
In the description of the present embodiment, the same reference numerals are given to portions having the same configurations as those of the capsule medical device 1 and the capsule medical device system 2 according to the first embodiment described above, and description thereof is omitted.

  A capsule medical device 1 ′ according to this embodiment includes two magnetic field sensor coils (hereinafter simply referred to as coils) 7 a and 7 b in the exterior 4. As shown in FIG. 10, the two coils 7 a and 7 b are wound so as to open obliquely with respect to the longitudinal axis R of the capsule medical device 1. The opening directions of the two coils 7a and 7b are set to be different from each other.

  In the example shown in FIG. 10, the two coils 7a and 7b are arranged so as to intersect at the same position in the longitudinal axis R direction. Thus, the two coils 7a and 7b have a common radial axis Q in a direction perpendicular to the paper surface of FIG. The magnetization direction of the permanent magnet 12 is arranged in parallel to the radial axis Q, that is, in a direction perpendicular to the paper surface of FIG. Thereby, it is possible to prevent the magnetic field formed by the permanent magnet 12 from penetrating the two coils 7a and 7b as much as possible.

  Further, as shown in FIG. 9, the two coils 7 a and 7 b are connected to the filter 8 via the switching unit 52. The switching unit 52 is connected to the A / D converter control unit 20 and is operated in synchronization with the A / D converter 19 by a timing signal generated by the timing generation circuit 21 of the A / D converter control unit 20. It is supposed to be.

  Further, as shown in FIG. 9, the guidance signal processing unit 9 is provided with an identification information holding unit 53. The identification information holding unit 53 stores information such as the positions of the two coils 7a and 7b, the relative angle in the opening direction, the magnetization direction of the permanent magnet 12, and the relative positions of the coils 7a and 7b and the permanent magnet 12. When the capsule medical device 1 is operated, information stored in the identification information holding unit 53 is transmitted to the extracorporeal device 28 at least once via the wireless transmitter 10.

The operation of the capsule medical device 1 ′ and the capsule medical device system according to this embodiment configured as described above will be described below.
According to the capsule medical device system according to the present embodiment, by the operation of the position detection field generation unit 38 of the extracorporeal device 28, the position-detection magnetic field M ₂ by the signal generating coils 41 for detecting one position the capsule medical device 1 ′, Two induction signals are generated by the two coils 7a and 7b in the capsule medical device 1 ′. Two coils coils 7a, since 7b are open in different directions, except when the direction of the position detection magnetic field M ₂ coincides with the direction of the longitudinal axis R, the two induction signal are different.

  The position and posture of the capsule medical device 1 are determined by a total of six values including three coordinate values for specifying a three-dimensional position and three rotation angle values around each coordinate axis. According to the capsule medical device system according to the present embodiment, two induction signals can be obtained by a magnetic field from one position detection signal generation coil 41. Therefore, three or more signal generation coils 41 are arranged at different positions. Thus, six or more different guidance signals can be obtained from the capsule medical device 1 ′ having the same position and the same posture.

  In particular, in the capsule medical device 1 ′ according to the present embodiment, the coils 7a and 7b are arranged with the opening direction facing in a direction inclined with respect to the longitudinal axis R of the capsule medical device 1 ′. Even if a magnetic field is applied, different induction signals are generated in the coils 7a and 7b if the rotation angle around the longitudinal axis R is different. Thereby, the rotation angle around the longitudinal axis R of the capsule medical device 1 ′ can be easily detected.

  Thus, according to the capsule medical device 1 ′ and the capsule medical device system according to the present embodiment, all six degrees of freedom of the capsule medical device 1 ′ can be determined. Therefore, even when the direction of the guidance magnetic field and the magnetization direction of the permanent magnet 12 do not coincide with each other due to friction between the capsule medical device 1 'in the body cavity and the surrounding tissue, etc., this is detected. There is an advantage that the capsule medical device 1 ′ can be guided with accuracy.

Further, according to the capsule medical device 1 ′ according to the present embodiment, the induction signals generated in the two coils 7 a and 7 b are switched by the operation of the switching unit 52 and are filtered by the filter 8. Therefore, the filter 8 sends the guidance signal generated by the guidance magnetic field M ₁ to the guidance signal processing unit 9 in a attenuated state, and therefore the external device 3 calculates the position and orientation of the capsule medical device 1 ′ with high accuracy. It becomes possible.

Further, since the connection between the two coils 7a and 7b and the filter 8 is switched by the switching unit 52, only one filter 8 is required, and the capsule medical device 1 'can be downsized.
The switching of the connection between the coils 7a and 7b and the filter 8 by the switching unit 52 is also performed by the timing signal generated in the timing generation circuit 21, so that the operation is synchronized with the operation of the position detection magnetic field generation unit 38 of the extracorporeal device 28. And can save power.

In the capsule medical device 1 ′ according to the present embodiment, two coils 7 a and 7 b are provided. However, three or more coils may be provided instead.
In the present embodiment, the coils 7a and 7b are arranged at the same position in the longitudinal axis R direction and provided with the common radial axis Q. Instead, as shown in FIG. , May be arranged at different positions in the direction along the longitudinal axis R. In this case, the two coils 7 a and 7 b have parallel radial axes Q ₁ and Q _2, and the distance between the radial axes Q ₁ and Q ₂ is also stored in the identification information holding unit 53. You can do that.

  In the present embodiment, the guidance signal processing unit of the capsule medical device 1 ′ includes the identification information holding unit 53 that is read at least once after activation. Thereby, even when the capsule medical device 1 ′ having different performance and arrangement of the coils 7a and 7b is employed, the position and orientation thereof can be detected with high accuracy.

  Instead, the identification information holding unit 53 may be provided in the external control unit 29 ′ of the external device 3 as shown in FIG. In this case, it is necessary to use a capsule medical device 1 'of a predetermined type, but it is not necessary to read out the identification information after activation, and the storage capacity of the capsule medical device 1' Savings.

1 is an overall configuration diagram showing a capsule medical device system according to a first embodiment of the present invention. It is a block diagram of the capsule medical device system of FIG. It is a block diagram which shows the capsule medical device which concerns on this embodiment. It is a longitudinal cross-sectional view which shows the capsule medical device of FIG. It is a block diagram which shows the induction | guidance | derivation signal process part incorporated in the capsule medical device of FIG. It is a block diagram which shows the external apparatus of the capsule medical device system of FIG. It is a wave form diagram which shows an example of the induction | guidance | derivation signal induced | guided | derived to the magnetic field sensor coil in the capsule medical device of FIG. It is a wave form diagram which shows an example of the guidance signal input into a guidance signal process part in the capsule medical device of FIG. It is a block diagram which shows the capsule medical device which concerns on the 2nd Embodiment of this invention. It is a longitudinal cross-sectional view which shows the capsule medical device of FIG. It is a longitudinal cross-sectional view which shows the modification of the capsule medical device of FIG. It is a block diagram which shows the modification of the external device of the capsule medical device system of FIG.

Explanation of symbols

M ₁ magnetic field for guidance M ₂ magnetic field for position detection 1,1 ′ capsule medical device 2 capsule medical device system 3 external device 5 imaging unit (biological information detection device)
7, 7a, 7b Coil 8 Filter (filter device)
9 Induction signal processing unit (induction signal processing device)
10 Wireless transmitter (wireless transmitter)
12 Permanent magnet (magnet)
30 Guidance magnetic field generator (guidance magnetic field generator)
33 Wireless receiver (wireless receiver)
34 Data separation unit (guidance signal extraction device)
38 Magnetic field generator for position detection (magnetic field generator for position detection)
43 Position / Direction Calculation Unit (Position / Direction Calculation Device)
52 Switching unit (switching device)

Claims (12)

A biological information detection device for detecting biological information in a body cavity;
A magnet that generates a driving force in response to a magnetic field for guidance acting from outside the body;
A coil that receives a position detecting magnetic field acting from outside the body and generates an induction signal;
A filter device connected to the coil and attenuating an induced signal component caused by the guidance magnetic field incident on the coil;
A wireless transmission device that transmits the guidance signal that has passed through the filter device and the biological information detected by the biological information detection device to the outside,
The opening direction of the coil and the direction of the magnetic field formed by the magnet at the position of the coil are substantially orthogonal,
A capsule medical device provided with two or more coils, wherein the opening directions of the coils are different.   The capsule medical device according to claim 1, wherein the coils are arranged at the same position. A biological information detection device for detecting biological information in a body cavity;
A magnet that generates a driving force in response to a magnetic field for guidance acting from outside the body;
A coil that receives a position detecting magnetic field acting from outside the body and generates an induction signal;
A filter device connected to the coil and attenuating an induced signal component caused by the guidance magnetic field incident on the coil;
A wireless transmission device that transmits the guidance signal that has passed through the filter device and the biological information detected by the biological information detection device to the outside,
Holding identification information necessary to detect the position and direction by the guidance signal;
Two or more coils are provided, and the identification information includes a relative position of the coils and a relative angle in the opening direction,
A capsule medical device in which the wireless transmission device transmits the identification information to the outside.   The capsule medical device according to claim 3, wherein the identification information includes a relative position and a relative angle of the coil, a relative position between the coil and the magnet, and a relative angle between an opening direction of the coil and a magnetization direction of the magnet. .   The capsule medical device according to claim 1, further comprising a switching device that switches connection between the two or more coils and the filter device. An induction signal processing device that processes the induction signal that has passed through the filter device and inputs the processed signal to a wireless transmission device;
The capsule medical device according to claim 1, wherein the guidance signal processing device and the biological information detection device are operated in synchronization.   The capsule medical device according to claim 6, wherein the switching device and the biological information detection device are operated in synchronization. A capsule medical device according to any one of claims 1 to 7,
An external device disposed outside the body,
A wireless receiver that receives the signal transmitted from the wireless transmitter;
An induction signal extraction device for extracting the induction signal from a signal received by the wireless reception device;
A position / direction calculation device that calculates the position or orientation of the capsule medical device based on the guidance signal extracted by the guidance signal extraction device;
A guidance magnetic field generator for generating the guidance magnetic field;
A capsule medical device system comprising: a position detection magnetic field generation device that generates the position detection magnetic field.   The position direction calculation device processes the induction signal extracted by the induction signal extraction device and generates a specific frequency signal having a frequency substantially the same as the frequency of the position detection magnetic field generated by the position detection magnetic field generation device. The capsule medical device system according to claim 8, wherein the capsule medical device system extracts and calculates the position and orientation of the capsule medical device based on the extracted specific frequency signal. A capsule medical device according to claim 3 or claim 4,
An external device disposed outside the body,
A wireless receiver that receives the signal transmitted from the wireless transmitter;
An information extraction device for extracting the induction signal and the identification information from the signal received by the wireless reception device;
A position / direction calculating device that calculates the position and orientation of the capsule medical device and the magnetization direction of the magnet based on the guidance signal and identification information extracted by the information extracting device;
A guidance magnetic field generator for generating the guidance magnetic field;
A capsule medical device system comprising: a position detection magnetic field generation device that generates the position detection magnetic field. A capsule medical device according to claim 1;
An external device disposed outside the body,
A wireless receiver that receives the signal transmitted from the wireless transmitter;
An information extraction device for extracting the induction signal from the signal received by the wireless reception device;
An identification information holding device for holding identification information including a relative position of two or more coils of the capsule medical device and a relative angle in the opening direction;
A position / direction calculation device that calculates the position and orientation of the capsule medical device and the magnetization direction of the magnet based on the identification information read from the identification information holding device and the guidance signal extracted by the information extraction device;
A guidance magnetic field generator for generating the guidance magnetic field;
A capsule medical device system comprising: a position detection magnetic field generation device that generates the position detection magnetic field.   The capsule medical device according to any one of claims 8 to 11, wherein the guidance magnetic field generation device is controlled based on the position and orientation of the capsule medical device calculated by the position direction calculation device and the magnetization direction of the magnet. system.

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