JP4823665B2 - Capsule type medical device and its guidance system - Google Patents

Description

The present invention relates to a capsule medical apparatus and the induction system.

2. Description of the Related Art Conventionally, a capsule type comprising a permanent magnet having a helical projection extending along its longitudinal axis on the outer peripheral surface of a substantially cylindrical capsule and having a magnetic pole arranged in a direction perpendicular to the longitudinal axis in the capsule A medical device is known (for example, refer to Patent Document 1).
According to this capsule-type medical device, by rotating an external magnetic field formed in the working space around the longitudinal axis of the capsule, the permanent magnet tends to rotate its magnetic pole direction along the direction of the external magnetic field. Can be used to rotate the capsule around the longitudinal axis. Since a spiral protrusion is provided on the outer peripheral surface of the capsule, when the capsule is rotated around the longitudinal axis while the spiral protrusion is in contact with an external tissue or the like, the spiral protrusion causes Rotational motion about the longitudinal axis is converted into propulsion motion along the longitudinal axis. As a result, the capsule can be moved in the longitudinal direction and guided to a desired position.

Moreover, a capsule medical device is known in which a permanent magnet having a magnetic pole disposed in the longitudinal axis direction is accommodated in a substantially cylindrical capsule (see, for example, Patent Document 2).
According to this capsule medical device, the direction of the capsule can be changed by forming an external magnetic field in the working space in an arbitrary direction and displacing the permanent magnet along the direction of the external magnetic field. it can. In addition, the capsule can be propelled in the longitudinal direction by using a gradient magnetic field as the external magnetic field.
JP 2004-255174 A JP 2003-111720 A

  However, in the capsule medical device guidance system of Patent Document 2, it is necessary to accurately form a three-dimensional gradient magnetic field in order to properly guide the capsule medical device in the body, which complicates the device. There is a problem. In addition, in the method of obtaining a propulsive force by a gradient magnetic field, there is a problem that fine speed and position control becomes difficult.

On the other hand, in the capsule medical device guidance system disclosed in Patent Document 1, the capsule's rotational motion is converted into a longitudinal motion by a helical projection provided on the outer peripheral surface of the cylindrical capsule. The speed and position can be controlled accurately according to the lead of the spiral protrusion by controlling the number of rotations of the capsule. In addition, it is not necessary to employ a gradient magnetic field as an external magnetic field, and a magnetic field having a uniform intensity is rotated, so that the configuration of the apparatus can be simplified.
However, the capsule medical device of Patent Document 1 is configured mainly for the purpose of propulsion along the longitudinal axis direction, and has a disadvantage that it cannot be easily changed in a desired direction.

The present invention has been made in view of the above-described circumstances, and easily and accurately performs a propulsion motion along the longitudinal axis direction and a change in the propulsion direction while simply configuring the guidance system. and its object is to provide a capsule medical device and its derived system capable.

In order to achieve the above object, the present invention provides the following means.
The present invention relates to a capsule medical device that is introduced into a body of a subject and is guided by an external magnetic field, and includes a substantially cylindrical capsule and a rotational motion around the longitudinal axis of the capsule. The propulsion mechanism that converts the magnetic field into the capsule, the magnet that is accommodated in the capsule, and the direction of the magnetic pole can be switched between the direction along the longitudinal axis and the direction intersecting the longitudinal direction, and the direction of the magnetic pole is switched. In each state, a capsule medical device is provided that includes fixing means for fixing the magnet to the capsule.

  According to the present invention, when the direction of the magnetic pole of the magnet accommodated in the capsule is switched to the direction along the longitudinal axis of the capsule and held at that position by the operation of the fixing means, an external magnetic field in an arbitrary direction is applied. The longitudinal axis of the capsule can be aligned with the direction along the direction of the external magnetic field. Therefore, the capsule can be directed in a desired direction by changing the direction of the external magnetic field.

In addition, by switching the direction of the magnetic pole of the magnet to a direction intersecting the longitudinal axis of the capsule and holding it at that position by the operation of the fixing means, when an external magnetic field rotating around the longitudinal axis of the capsule is applied, It can be rotated around its axis. Since the capsule is provided with a propulsion mechanism, when the capsule is rotated around the longitudinal axis, the capsule is linearly moved along the longitudinal axis by the operation of the propulsion mechanism. Therefore, the capsule can be propelled in the direction along the longitudinal axis.
The propulsion mechanism is preferably a spiral mechanism provided on the outer peripheral surface of the capsule.
Further, the present invention provides a capsule medical equipment induced by the external magnetic field is introduced into the body of a subject, a substantially cylindrical capsule contained within the capsule, the longitudinal axis direction of the magnetic poles the direction along the a magnet provided so as to be switched between a direction intersecting thereto, in each state of switching the direction of the magnetic poles, Encapsulate medical and a fixing means for fixing the magnet in the capsule Providing equipment.

In the above invention, the magnet is a permanent magnet, and the fixing means is engaged with the magnet at a position where the magnetic pole is oriented in the direction along the longitudinal axis and a position where the magnetic pole is oriented in a direction crossing the magnetic pole. It is good also as consisting of a member.
By doing so, the operation of the fixing means made of the engaging member ensures that the permanent magnet is held at either the position along the longitudinal axis of the capsule or at the position crossing the permanent magnet. be able to. Therefore, the direction change of the capsule and the propulsion of the capsule can be switched. In addition, what is necessary is just to apply an external force larger than an engagement force in order to cancel | release the engagement state by an engagement member.

In the above invention, the magnet is a permanent magnet, and the fixing means attracts the magnet at a position where the magnetic pole is oriented in a direction along the longitudinal axis and a position where the magnetic pole is oriented in a direction crossing the magnetic pole. It may be made of a material.
In this way, when the permanent magnet is disposed in a direction along the longitudinal axis of the capsule or in a direction crossing the permanent magnet, the permanent magnet is attracted and fixed to the fixing means made of a magnetic material at that position. Therefore, the direction change of the capsule and the propulsion of the capsule can be switched. In order to cancel the attracted state to the magnetic material and switch the direction of the magnetic pole of the permanent magnet, an external force larger than the attracting force may be applied.

Moreover, in the said invention, it is good also as providing the magnetic pole direction switching apparatus which switches the direction of the magnetic pole of this magnet.
By doing in this way, the direction change of a capsule and propulsion can be arbitrarily switched by switching the direction of the magnetic pole of a magnet reliably by the action | operation of a magnetic pole direction switching apparatus.

In the above invention, the magnet is a permanent magnet, and the fixing means is an electromagnet that is attracted to the magnet at a position where the magnetic pole is oriented in a direction along the longitudinal axis and a position where the magnetic pole is oriented in a direction crossing the magnetic pole. The magnetic pole direction switching device may be a magnetic pole switching device that switches the magnetic poles of the electromagnet.
In this way, by the operation of the fixing means made of an electromagnet, the magnet is attracted at either the position along the longitudinal axis of the capsule or the position crossing the longitudinal axis of the capsule. Can be fixed to the state. Further, by switching the magnetic poles of the electromagnets by the operation of the magnetic pole switching device, the attracted magnets can be separated by the magnetic repulsive force, and the positions can be switched easily and reliably.

In the above invention, the magnet may be a permanent magnet, and the magnetic pole direction switching device may be a motor that swings the magnet around an axis along the radial direction of the capsule.
By doing in this way, the direction change of a capsule and propulsion can be switched easily and reliably by rotating the magnet which consists of a permanent magnet by the action | operation of the magnetic pole direction switching apparatus which consists of a motor.

In the above invention, the magnet may be an electromagnet, and the fixing means and the magnetic pole direction switching device may be a magnetic pole switching device that switches and holds the magnetic poles of the electromagnet.
By doing so, the magnetic pole direction of the magnet made of an electromagnet can be switched between the direction along the longitudinal axis of the capsule and the direction intersecting the capsule by the operation of the magnetic pole switching device, and the capsule can be easily and reliably Can be switched between direction change and promotion.

The present invention also provides a magnetic field that generates any external magnetic field that is disposed outside the operating range of the capsule medical device and that acts on the magnet in the capsule medical device. Provided is a capsule medical device guidance system that includes a generator and a magnetic field controller that controls an external magnetic field applied to the magnet by the magnetic field generator.
According to the present invention, the external magnetic field is applied to the magnet in the capsule medical device by the operation of the magnetic field generator, and the external magnetic field is controlled by the magnetic field control device so that the magnet in the capsule is in the direction along the longitudinal axis of the capsule. The direction of the capsule and the propulsion can be selectively performed by switching to one of the directions intersecting with the direction. As a result, the capsule can be accurately guided in a desired direction.

In the above invention, a capsule direction detection device that detects the direction of the capsule medical device is provided, and the magnetic field control device is configured to operate in accordance with the direction of the capsule medical device detected by the capsule direction detection device. The direction of the external magnetic field at the position of the apparatus may be controlled.
In this manner, the direction of the external magnetic field that the magnetic field control device acts on the magnet in the capsule medical device is determined based on the detected direction of the capsule medical device by the operation of the capsule direction detection device. Can do. When the detected direction of the capsule medical device is the direction toward the target position, the direction of the magnet is switched to be propelled so as to be propelled, and when the direction is not toward the target position, the direction is changed. The direction of the magnet can be switched to change the direction.

The invention as a reference example of the present invention is any one of the capsule medical device guiding methods described above, wherein the direction of the magnetic pole of the magnet is switched to a direction crossing the longitudinal axis and fixed, and the circumference of the longitudinal axis is fixed. By applying a rotating external magnetic field, the capsule medical device is advanced in the longitudinal axis direction, the direction of the magnetic pole of the magnet is switched and fixed along the longitudinal axis, and an external magnetic field formed in an arbitrary direction is applied. Accordingly, a method of guiding a capsule medical device that changes the traveling direction of the capsule medical device is provided.

  According to the present invention, the capsule medical device can be easily and accurately guided by simply switching between the propulsion and direction change of the capsule medical device by simply switching the direction of the magnetic pole of the magnet built in the capsule medical device. be able to.

  According to the present invention, the propulsion along the longitudinal axis direction and the change of the propulsion direction can be easily switched with a simple configuration, and the effect that the guidance can be performed accurately and stably is achieved.

[First Embodiment]
Hereinafter, a capsule endoscope (capsule medical device) 1 according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.
As shown in FIG. 1, a capsule endoscope 1 according to this embodiment includes a capsule 2 and an imaging unit 3 that is accommodated in the capsule 2 and images an inner wall surface of a body cavity duct of a subject. And an induction magnetic field generation unit 4 and a permanent magnet (magnet) 5.

  The capsule 2 includes a cylindrical capsule main body 6 (hereinafter simply referred to as a main body) having a longitudinal axis R of the capsule endoscope 1 as a central axis, and a transparent and hemispherical distal end portion 6a covering the front end of the main body 6. And a hemispherical rear end 6b covering the rear end of the main body 6 to form a capsule container sealed with a watertight structure.

  Further, on the outer peripheral surface of the main body 6 of the capsule 2, a spiral portion (spiral mechanism, propulsion mechanism) 7 in which a wire having a circular cross section around the longitudinal axis R is spirally attached is attached. Thereby, when the main body 6 is rotated around the longitudinal axis R, the main body 6 is linearly moved in the direction along the longitudinal axis R by an amount of movement determined according to the lead of the spiral portion 7.

  The imaging unit 3 is opposed to the distal end portion, and includes an image sensor 8 that captures an image of the inner wall surface of the body cavity passage of the subject, and an LED (Light Emitting Diode) 9 that illuminates the inner wall surface of the body cavity conduit. It has. The reflected light from the inner wall surface of the body cavity duct illuminated by the operation of the LED 9 can be acquired as an image by the image sensor 8.

For example, a CMOS (Complementary Metal Oxide Semiconductor) or a CCD can be used as the image sensor 8.
A plurality of LEDs 9 are arranged on the support member 9a arranged on the distal end portion 6a side at intervals in the circumferential direction about the longitudinal axis R.

  The induction magnetic field generator 4 is a resonance circuit configured by connecting a magnetic induction coil 10 and a capacitor 11, and is resonated by an alternating magnetic field having a predetermined frequency supplied from the outside. A magnetic core (not shown) is disposed inside the magnetic induction coil 10. For the magnetic core, a magnetic material is suitable in addition to ferrite, and iron, nickel, permalloy, cobalt, or the like can also be used. As a result, an alternating magnetic field having a large amplitude used for position detection is generated.

As shown in FIGS. 1 and 2, the permanent magnet 5 is formed in a cylindrical shape that is slightly smaller than the inner diameter of the body 6 of the capsule 2, and one semi-cylindrical part is an N pole and the other semi-cylindrical part is an S pole. Is magnetized. The permanent magnet 5 is attached to the inner surface of the main body 6 by a rotary shaft 12 penetrating the boundary portion between the N pole and the S pole in the diametrical direction, and is provided rotatably around the rotary shaft 12.
The permanent magnet 5 and the rotating shaft 12 are fitted to each other so that a predetermined frictional force is generated between them.

  A stopper 13 is disposed in the vicinity of the permanent magnet 5. The stopper 13 is a state in which the permanent magnet 5 rotates around the rotation axis 12 and the magnetic poles are arranged in the longitudinal axis R direction (the state shown in FIG. 2B) and in the direction perpendicular to the longitudinal axis R. In the state shown in FIG. 2 (a), the permanent magnets 5 are arranged at positions where they abut against the side surfaces of the permanent magnets 5 to prevent further rotation of the permanent magnets 5.

Next, a guidance system 30 and a guidance method for a capsule endoscope according to an embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 3, the guidance system 30 according to the present embodiment is inserted into the body cavity from the mouth or anus of the subject, optically images the inner wall surface of the body cavity duct, and wirelessly transmits the image signal. The capsule endoscope 1 that is transmitted in the above, the position detection system 50 that detects the position of the capsule endoscope 1, and the capsule type based on the detected position of the capsule endoscope 1 and the operator's instruction A magnetic guidance device 70 for guiding the endoscope 1 and an image display device 80 for displaying an image signal transmitted from the capsule endoscope 1 are provided.

  As shown in FIG. 3, the magnetic guidance device 70 includes a three-axis Helmholtz coil unit (magnetic field generator) 71 that generates a parallel external magnetic field (substantially uniform magnetic field) M that drives the capsule endoscope 1, and a three-axis A Helmholtz coil driver 72 that amplifies and controls the current supplied to the Helmholtz coil unit 71, a magnetic field control circuit 73 that controls the direction of a parallel magnetic field that drives the capsule endoscope 1, and a capsule endoscope that is input by a practitioner And an input device 74 that outputs the traveling direction of 1 to the magnetic field control circuit 73. Further, in the input device 74, either the propulsion mode or the direction change mode can be selected as the guidance mode of the capsule endoscope 1.

  As shown in FIGS. 3 to 5, the three-axis Helmholtz coil unit 71 is formed in a substantially rectangular shape. The 3-axis Helmholtz coil unit 71 includes three pairs of Helmholtz coils 71X, 71Y, 71Z facing each other, and each pair of Helmholtz coils 71X, 71Y, 71Z corresponds to the X, Y, and Z axes in FIG. Are arranged so as to be substantially vertical. Helmholtz coils arranged substantially perpendicular to the X, Y, and Z axes will be referred to as Helmholtz coils 71X, 71Y, and 71Z, respectively.

The Helmholtz coils 71X, 71Y, 71Z are arranged so as to form a rectangular parallelepiped space therein. The rectangular parallelepiped space is a working space of the capsule endoscope 1 as shown in FIG. 3, and is also a space where the subject A is arranged as shown in FIGS. .
In this embodiment, the Helmholtz coils 71X, 71Y, and 71Z are described. However, as shown in FIGS. 3 to 5, the coils may be formed of square coils, and the Helmholtz coil conditions must be strictly satisfied. It's not something you have to do.

The Helmholtz coil driver 72 includes Helmholtz coil drivers 72X, 72Y, and 72Z that control the Helmholtz coils 71X, 71Y, and 71Z, respectively.
The magnetic field control circuit 73 receives data indicating the current direction of the capsule endoscope 1 (direction of the longitudinal axis R of the capsule endoscope 1) from the position detection device 50A of the position detection system 50, and performs a treatment. The guidance mode data input by the person through the input device 74 and the direction of travel of the capsule endoscope 1 are input.

  When the guidance mode data is input to the magnetic field control circuit 73, the magnetic field control circuit 73 instantaneously generates an external magnetic field M for switching the magnetic pole direction of the permanent magnet 45 based on the direction data of the capsule endoscope 1. Has been generated. That is, when the traveling mode is input as the guidance mode data, the magnetic field control circuit 73 instantaneously generates the external magnetic field M in the direction orthogonal to the longitudinal axis R of the capsule 2 in the Helmholtz coil unit 71. As shown in (a), the direction of the permanent magnet 45 is switched to a direction orthogonal to the longitudinal axis R of the capsule. When the direction change mode is input as the guidance mode data, the magnetic field control circuit 73 instantaneously generates the external magnetic field M in the direction along the longitudinal axis R of the capsule 2 in the Helmholtz coil unit 71, as shown in FIG. As shown in (b), the direction of the permanent magnet 45 is switched to the direction along the longitudinal axis R of the capsule 2.

  The magnetic field control circuit 73 outputs a signal for controlling the Helmholtz coil drivers 72X, 72Y, 72Z according to each guidance mode, and rotational phase data of the capsule endoscope 1 is transmitted to the image display device 80. It is output.

In addition, as the input device 74, an input device that indicates the traveling direction of the capsule endoscope 1 by tilting the joystick is used.
The input device 74 may be a joystick type as described above, or may be another type of input device such as an input device that indicates the direction of travel by pressing a button in the direction of travel. .

  As shown in FIG. 3, the position detection system 50 includes a drive coil 51 that generates an induction magnetic field in the magnetic induction coil 10 in the capsule endoscope 1 and a sense coil that detects the induction magnetic field generated by the magnetic induction coil 10. 52 and a position detection device 50A that calculates the position of the capsule endoscope 1 based on the induced magnetic field detected by the sense coil 52 and controls the AC magnetic field formed by the drive coil 51.

  Between the position detection device 50A and the drive coil 51, from the sine wave generation circuit 53 that generates an alternating current based on the output from the position detection device 50A and from the sine wave generation circuit 53 based on the output from the position detection device 50A. A drive coil driver 54 that amplifies the input alternating current and a drive coil selector 55 that supplies an alternating current to the drive coil 51 selected based on the output from the position detection device 50A are arranged.

  Between the sense coil 52 and the position detection device 50A, a sense coil selector 56 that selects an alternating current including position information of the capsule endoscope 1 from the sense coil 52 based on an output from the position detection device 50A. And a sense coil receiving circuit 57 that extracts an amplitude value from the alternating current that has passed through the sense coil selector 56 and outputs it to the position detection device 50A.

  As shown in FIG. 3, the image display device 80 receives an image based on an image receiving circuit 81 that receives an image transmitted from the capsule endoscope 1, a received image signal, and a signal from the magnetic field control circuit 73. Display unit (display means, image control means) 82.

The operation of the capsule endoscope 1 and the guiding system 30 according to the present embodiment configured as described above will be described below.
In order to observe the inside of the body cavity of the subject A using the capsule endoscope 1 and the guidance system 30 according to the present embodiment, as shown in FIG. The body is inserted into the body cavity from the mouth or anus of the subject A lying in the detection system 50 and the magnetic guidance device 70. The position of the inserted capsule endoscope 1 is detected by the position detection system 50, and the magnetic guidance device 70 guides the inside of the body cavity of the subject A to the vicinity of the affected part. The capsule endoscope 1 captures an image of the inner wall surface of the body cavity duct during guidance to the affected area and in the vicinity of the affected area. Then, the imaged data on the inner wall surface of the body cavity conduit and the data near the affected area are transmitted to the image display device 80. The image display device 80 displays the transmitted image on the display unit 82.

  In the position detection system 50, as shown in FIG. 3, first, the sine wave generation circuit 53 generates an alternating current based on the output from the position detection device 50A, and the alternating current is output to the drive coil driver 54. The frequency of the generated alternating current is a frequency within a range from several kHz to 100 kHz.

  The alternating current is amplified by the drive coil driver 54 based on an instruction from the position detection device 50 </ b> A and output to the drive coil selector 55. The amplified alternating current is supplied to the drive coil 51 selected by the position detecting device 50A in the drive coil selector 55. The alternating current supplied to the drive coil 51 forms an alternating magnetic field in the working space of the capsule endoscope 1.

In the magnetic induction coil 10 of the capsule endoscope 1 located in the AC magnetic field, an induced electromotive force is generated by the AC magnetic field and an induced current flows. When an induction current flows through the magnetic induction coil 10, induction magnetism is generated and an alternating magnetic field is formed.
Further, since the magnetic induction coil 10 forms a resonance circuit together with the capacitor 11, if the period of the AC magnetic field coincides with the resonance frequency of the resonance circuit, the induced current flowing through the resonance circuit (magnetic induction coil 10) increases and forms. The AC magnetic field that is generated also becomes stronger. Furthermore, since the core member made of dielectric ferrite is disposed at the center of the magnetic induction coil 10, the magnetic flux is easily collected on the core member, and the formed AC magnetic field is further strengthened.

The induced AC magnetic field generates an induced electromotive force in the sense coil 52, and an AC voltage (magnetic information) including position information of the capsule endoscope 1 is generated in the sense coil 52. This AC voltage is input to the sense coil receiving circuit 57 via the sense coil selector 56, and the amplitude value of the AC voltage is extracted.
The sense coil receiving circuit 57 stores an amplitude value corresponding to one cycle obtained by sweeping the sine wave signal generated by the sine wave generating circuit 53 in the vicinity of the resonance frequency of the resonance circuit, and collects the amplitude values for one cycle. Output to the position detection device 50A.

As shown in FIG. 6, the amplitude value of the AC voltage described above varies greatly depending on the relationship between the AC magnetic field formed by the drive coil 51 and the resonance frequency of the resonance circuit 4. In FIG. 6, the horizontal axis represents the frequency of the AC magnetic field, and the vertical axis represents the gain change (dBm) and phase change (degree) of the AC voltage flowing through the resonance circuit 4. The gain change is represented by a solid line, and shows that the maximum value is obtained at a frequency lower than the resonance frequency, the gain change is zero at the resonance frequency, and the minimum value is taken at a frequency higher than the resonance frequency. Further, the phase change is represented by a broken line, which indicates that it is most delayed at the resonance frequency.
Depending on the measurement conditions, there may be a minimum value at a frequency lower than the resonance frequency, a maximum value at a frequency higher than the resonance frequency, and the phase most advanced at the resonance frequency.

The position detection device 50 </ b> A regards the amplitude difference between the maximum and minimum amplitude values before and after the resonance frequency as the output from the sense coil 52. Then, the position detection device 50A solves the simultaneous equations related to the position, direction, and magnetic field strength of the capsule endoscope 1 based on the amplitude difference obtained from the plurality of sense coils 52, thereby enabling the capsule endoscope The position of the mirror 1 is obtained.
Thus, by using the amplitude difference as the output of the sense coil 52, the change in the amplitude due to the change in the magnetic field strength due to the environmental condition (for example, temperature) can be canceled, and it is affected by the environmental condition. Therefore, the position of the capsule endoscope 1 can be obtained with stable accuracy.

The position detection device 50A instructs the drive coil driver 54 on the amplification factor of the alternating current supplied to the drive coil 51 based on the position of the capsule endoscope 1 obtained by the calculation. This amplification factor is set so that the induction magnetic field generated by the magnetic induction coil 10 can be detected by the sense coil 52.
Further, the position detection device 50 selects a drive coil 51 that forms a magnetic field, and outputs an instruction to the drive coil selector 55 to supply an alternating current to the selected drive coil 51.

  In the magnetic guidance device 70, first, as shown in FIG. 3, the practitioner selects the guidance mode of the capsule endoscope 1 to the magnetic field control circuit 73 via the input device 74. When the traveling mode is selected as the guiding mode, a relatively large external magnetic field M is instantaneously formed in a direction orthogonal to the longitudinal axis R direction of the capsule 2 detected by the position detection system 50. As a result, a torque exceeding the static friction force generated between the permanent magnet 5 and the rotating shaft 12 is generated, and the permanent magnet 5 rotates around the rotating shaft 12 as shown in FIG. The magnetic poles are directed in a direction perpendicular to the longitudinal axis R. The permanent magnet 5 abuts against the stopper 13 when the magnetic pole is directed in a direction perpendicular to the longitudinal axis R, and is stopped by a static frictional force with the rotating shaft 12.

In this state, when the practitioner instructs the traveling direction via the input device 74, the direction of the capsule endoscope 1 (the direction of the instructed traveling direction and the position detection device 50 </ b> A input by the operation of the magnetic field control circuit 73 ( The direction of the external magnetic field M applied to the capsule endoscope 1 and the rotation direction are determined based on the longitudinal axis R direction).
Then, the generated magnetic field strength of each Helmholtz coil 71X, 71Y, 71Z necessary for forming the direction of the external magnetic field M is calculated, and the current value required to generate the external magnetic field M is calculated.

The current value data supplied to the Helmholtz coils 71X, 71Y, 71Z is output to the corresponding Helmholtz coil drivers 72X, 72Y, 72Z. The Helmholtz coil drivers 72X, 72Y, 72Z are supplied with currents based on the input data. Are controlled to supply current to the corresponding Helmholtz coils 71X, 71Y, 71Z.
The Helmholtz coils 71X, 71Y, 71Z to which the current is supplied generate magnetic fields corresponding to the current values, respectively, and these magnetic fields are combined to generate a parallel external magnetic field M having a magnetic field direction determined by the magnetic field control circuit 73. Is formed.

  The rotation period of the external magnetic field M is controlled to about 0 Hz to several Hz, and the rotation direction of the capsule endoscope 1 around the longitudinal axis R is controlled by controlling the rotation direction of the external magnetic field M. . Thereby, the permanent magnet 5 is directed in the direction along the rotating external magnetic field M, and the capsule 2 to which the permanent magnet 5 is fixed is rotated around the longitudinal axis R thereof. Then, by the action of the spiral portion 7 provided on the outer peripheral surface of the capsule 2, the rotational motion around the longitudinal axis R of the capsule 2 is converted into a rectilinear motion along the longitudinal axis R, so that the capsule endoscope 1 is input to the input device 74. Is propelled at a speed determined by the rotational speed of the external magnetic field M and the lead of the spiral portion 7 in the direction indicated by.

  The permanent magnet 5 is not rotated when the external magnetic field M formed when the traveling mode is selected as the guidance mode is in the direction along the rotation axis 12 or in the opposite direction in the radial direction. . In order to avoid this, for example, the phase around the longitudinal axis R of the capsule 2 is obtained by processing the image acquired by the image sensor 8, and the direction in which the external magnetic field M is applied is determined based on this phase. And it is sufficient.

  On the other hand, when the direction change mode is selected as the guidance mode, a relatively large external magnetic field M is instantaneously formed in the direction along the longitudinal axis R direction of the capsule 2 detected by the position detection device 50A. As a result, a torque exceeding the static friction force generated between the permanent magnet 5 and the rotating shaft 12 is generated, and the permanent magnet 5 rotates around the rotating shaft 12 as shown in FIG. The magnetic poles are directed in the direction along the longitudinal axis R. The permanent magnet 5 stops by striking against the stopper 13 when the magnetic pole is directed in the direction along the longitudinal axis R, and is held in a stopped state by a static frictional force with the rotating shaft 12.

After that, based on the input from the input device 74, the angle of the external magnetic field M formed in the direction along the longitudinal axis R of the capsule 2 is gradually changed, thereby generating a rotational force in the capsule 2 and the direction. Can be converted.
At the time of switching from the traveling mode to the direction change mode, the direction of the magnetic pole of the permanent magnet 5 is switched and guided only by applying the external magnetic field M in the direction along the longitudinal axis R of the capsule 2 regardless of the direction of the permanent magnet 5. The mode can be easily switched.

In the capsule endoscope 1, the mounted image sensor 8 images the wall surface in the body cavity line of the subject A illuminated by the LED 9, and the acquired image is transmitted to the image display device 80. Is done.
In the image display device 80, the image receiving circuit 81 receives the image information transmitted from the capsule endoscope 1, and the received image information is displayed on the display unit 82.

  Further, when the guidance mode is the traveling mode, the display unit 82 is in the direction opposite to the rotation direction of the capsule endoscope 1 based on the rotation phase data of the capsule endoscope 1 input from the magnetic field control circuit 73. The image signal is displayed after being rotated. As a result, regardless of the rotational phase of the capsule endoscope 1, the image always remains at a predetermined rotational phase, that is, as if the capsule endoscope 1 does not rotate around the longitudinal axis R. An image that is traveling in the direction along the direction can be displayed on the display unit 82.

  Accordingly, when the capsule endoscope 1 is guided in the advance mode while the operator visually observes the image displayed on the display unit 82, the displayed image is an image that rotates as the capsule endoscope 1 rotates. Compared with a case where the image displayed as described above is displayed as an image of a predetermined rotational phase, it is easier for the practitioner to see and the capsule endoscope 1 is easily guided to a predetermined position.

  As described above, according to the capsule endoscope 1 and the guidance system 30 thereof according to the present embodiment, the built-in permanent magnet 5 can be obtained simply by causing the external magnetic field M in a specific direction to act on the capsule endoscope 1. The direction of the magnetic pole can be switched to set either the traveling mode or the direction changing mode. Therefore, in the advance mode, the capsule endoscope 1 can be accurately advanced in the direction of the longitudinal axis R, and in the direction change mode, the capsule endoscope 1 can be stably oriented in a desired direction. As a result, the capsule endoscope 1 can be guided accurately and stably in the body of the subject A, and a desired examination can be performed.

  In the present embodiment, the fixing means for the permanent magnet 5 is exemplified by a means for fixing the permanent magnet 5 by a static frictional force with the rotary shaft 12 that rotatably supports the permanent magnet 5. 7 and FIG. 8, the click mechanism is provided with a concave portion 5a in the permanent magnet 5, and a ball 14a and a spring 14b that engage with the concave portion 5a of the permanent magnet 5 at each position in the traveling mode and the direction change mode. 14 may be provided in two places. By doing in this way, the state of each guidance mode can be maintained more reliably.

  Instead of this, as shown in FIGS. 9 and 10, as the permanent magnet 5, a cylindrical shape centering on the rotating shaft 12 may be adopted. By doing in this way, the recessed part 5a can be provided in two places 90 degree apart along the surrounding surface of the permanent magnet 5, and the click mechanism 14 provided with the ball | bowl 14a and the spring 14b can be made into one place.

  In addition, as shown in FIG. 11, two recesses 5a are formed deeper, grooves 5b are provided to communicate between the recesses 5a in the circumferential direction, and a shaft 14a 'is disposed in place of the balls 14a. Also good. Thus, when the tip of the shaft 14a 'engages with the recess 5a, the shaft 14a' abuts against the inner wall of the groove 5b to prevent further rotation of the permanent magnet 5, and the operating range of the permanent magnet 5 Can be limited to within a range of 90 °.

  Moreover, although the columnar permanent magnet 5 is employed, a spherical permanent magnet (not shown) may be employed instead. By doing in this way, the volume of a permanent magnet can be enlarged and the magnetic force which a permanent magnet generates can be ensured large. As a result, the strength of the external magnetic field M for driving the capsule endoscope 1 can be reduced, and the magnetic field generator 71 disposed outside the body can be downsized. In addition, the ball 14a or the shaft 14a 'urged by the coil spring 14b is engaged with the recess 5a provided in the permanent magnet 5, but instead, a protrusion (not shown) provided on a leaf spring (not shown). (Not shown) may be engaged with the recess 5a.

  Instead of this, a clutch mechanism 15 may be arranged between the capsule 2 and the permanent magnet 5 as shown in FIG. The clutch mechanism 15 is always turned off and fixed so that the permanent magnet 5 does not rotate. When the induction mode is switched, the clutch mechanism 15 is turned on and released so that the permanent magnet 5 can freely rotate. Yes. By doing in this way, there exists an advantage that fixation and separation | separation with respect to the capsule 2 of the permanent magnet 5 can be performed reliably, and a guidance mode can be switched more easily. Further, by always turning off the battery, it is possible to prevent the battery from being consumed.

  In addition, the permanent magnet 5 can freely rotate around the rotation axis 12 and the stopper 13 that contacts the permanent magnet 5 in FIGS. 1 and 2 can be made of a magnetic material as a fixing means of the permanent magnet 5. Good. By doing in this way, when the permanent magnet 5 rotates at the time of switching of the induction mode and hits the stopper 13, the permanent magnet 5 is attracted and fixed to the stopper 13 made of a magnetic material, and is held in each state. On the other hand, when switching the induction mode, the permanent magnet 5 can be rotated and moved to another state by applying an external magnetic field M capable of generating torque that overcomes the magnetic attractive force between the permanent magnet 5 and the stopper 13. And it is sufficient.

  Furthermore, in the capsule endoscope 1 according to the present embodiment, the direction of the magnetic pole of the permanent magnet 5 is switched by the action of the external magnetic field M. Instead, the magnetic pole of the permanent magnet 5 is placed in the capsule 2. An actuator for switching the direction may be arranged. As an actuator, for example, as shown in FIG. 13, a motor 16 that is actuated by a command signal from the outside is arranged on the rotating shaft 12 of the permanent magnet 4, and the permanent magnet 5 is rotated by the operation of the motor 16. The direction may be switched.

  Further, for example, as shown in FIG. 14, as a stopper, an electromagnet 17 that abuts against the permanent magnet 5 is disposed, and the magnetic pole of the portion that abuts against the permanent magnet 5 is switched to change the direction of the magnetic pole of the permanent magnet 5. Also good. The electromagnet 17 is connected to a magnetic pole direction switching device (not shown) that switches the direction of the magnetic pole of the electromagnet 17 in accordance with an external command signal.

  In the example shown in FIG. 14, when the traveling mode is selected, the corresponding magnetic pole of the electromagnet 17 is arranged so that the N pole of the permanent magnet 5 is attracted to the electromagnet 17 as shown in FIG. Set to S pole. Thereby, the permanent magnet 5 is fixed in a state in which the magnetic poles are arranged in the direction orthogonal to the longitudinal axis of the capsule 2. After the magnetic pole of the permanent magnet 5 is once fixed, the permanent magnet 5 can be held in an attracted state by using the electromagnet 17 as a magnetic body by turning off the electromagnet 17. Thereby, consumption of the battery can be suppressed.

  On the other hand, when the direction change mode is selected, as shown in FIG. 14B, the magnetic pole of the electromagnet 17 that has attracted the N pole of the permanent magnet 5 is changed to the N pole. Thereby, a magnetic repulsive force between the permanent magnet 5 and the electromagnet 17 is generated, and the permanent magnet 5 is rotated in a direction away from the electromagnet 17.

  Immediately thereafter, as shown in FIG. 14C, the S pole of the permanent magnet 5 is attracted to the electromagnet 17 by setting the magnetic pole on the opposite side of the electromagnet 17 to the N pole. Thereby, the permanent magnet 5 is fixed in a state in which the magnetic poles are arranged in the direction along the longitudinal axis R of the capsule 2. Therefore, the guidance mode can be switched quickly by switching the direction of the magnetic pole of the permanent magnet 5 more simply and reliably.

In the present embodiment, the direction of the magnetic pole of the permanent magnet 5 in the traveling mode is set to a direction orthogonal to the longitudinal axis R. Instead, it intersects the longitudinal axis R at an angle smaller than 90 °. The direction may be set.
In addition, the direction of the external magnetic field M is set based on the image acquired by the image sensor 8 when switching from the direction change mode to the traveling mode. Instead, the permanent magnet 5 in the direction change mode is set. The magnetic poles may be arranged in a direction slightly angled from the direction along the longitudinal axis R toward the traveling mode side. In this way, a slight rotational torque can be generated by an external magnetic field M that is arbitrarily added (or rotated) perpendicular to the longitudinal axis R, and the rotational shaft 12 causes the external magnetic field to be generated by the rotational torque. By moving to a position orthogonal to M, the permanent magnet 5 may be easily switched to the traveling mode.

Next, a capsule endoscope according to a second embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 15, the capsule endoscope 1 ′ according to the present embodiment has a circular arc portion 5c, a sector-shaped permanent magnet 5 ′ having a central angle of 90 °, and the permanent magnet 5 ′. And a case 18 for rotatably accommodating the housing.

The case 18 includes two side surfaces sandwiching the arc portion 5c of the permanent magnet 5 'and a wall surface 18a made of a magnetic material capable of adsorbing the arc surface 5c, and a wall surface 18b made of another nonmagnetic material.
Permanent magnet 5 'has one side magnetized to N pole and the arc side is magnetized to S pole. As a result, as shown in FIG. 15A, the magnetic pole of the permanent magnet 5 ′ is arranged in the direction along the longitudinal axis R of the capsule 2 in a state where one side surface of the permanent magnet 5 ′ is attracted to the one wall surface 18 a. Thus, the guidance mode is set to the direction change mode. Further, as shown in FIG. 15 (b), the arc portion 5c rolls while adsorbing to the wall surface 18a, and as shown in FIG. 15 (c), the other side surface is adsorbed to the other wall surface 18a. The magnetic poles of the permanent magnet 5 ′ are arranged in a direction perpendicular to the longitudinal axis R of the capsule 2, whereby the induction mode is set to the traveling mode.

  According to the capsule endoscope 1 ′ according to the present embodiment configured as described above, in the case 18 due to the action of the external magnetic field M, similarly to the capsule endoscope 1 according to the first embodiment. The induction mode can be easily switched by rolling the permanent magnet 5 '. Therefore, according to the present embodiment, the capsule endoscope 1 ′ can be configured with a simple mechanism, has good assemblability, and can be freely switched between the traveling mode and the direction change mode at low cost. Can be provided.

  In the present embodiment, the permanent magnet 5 'slides and moves in the case 18 without changing its posture by rolling the arc portion 5c of the permanent magnet 5' while adsorbing it to the wall surface 18a made of a magnetic material. It was decided to prevent that. Instead of this, as shown in FIG. 16, the arc portion 5 c and gears 5 d and 18 c that mesh with each other on the wall surface 18 a of the case 18 on which the arc portion 5 c rolls may be provided. In this way, the permanent magnet 5 'is prevented from slipping with respect to the case 18, and the direction of the magnetic pole can be switched reliably.

  Further, as shown in FIG. 17, a pin 5 e may be provided in the permanent magnet 5 ′, and a cam groove 18 d for guiding the pin 5 e may be provided in the case 18. In this way, similarly to the magnetic gears 5d and 18c, the movement of the permanent magnet 5 'can be uniquely guided, and the direction of the magnetic pole can be reliably switched when the induction mode is switched. it can.

  Further, the permanent magnet 5 'having the circular arc part 5c is not limited to the one-quarter fan-shaped one, and a cylindrical permanent magnet 5' is adopted as shown in FIG. Also good. In this case, in order to limit the degree of freedom of the permanent magnet 5 ′ in the case 18, wall surfaces made of permanent magnets arranged at two locations on the case 18 with the south and north poles facing the inside of the case 18, respectively. What is necessary is just to provide 18e.

Next, a capsule endoscope 1 ″ according to a third embodiment of the present invention will be described below with reference to FIG.
Unlike the capsule endoscopes 1 and 1 'according to the first and second embodiments, the capsule endoscope 1 ″ according to the present embodiment is switched from the outside by switching the guidance mode by the external magnetic field M. In this method, the induction mode is switched by a mechanical pressing force F.

  As shown in FIG. 19A, a capsule endoscope 1 ″ according to this embodiment includes a rectangular parallelepiped permanent magnet 5 ″, a pedestal 19 that holds the permanent magnet 5 ″ in an attracted state, The pedestal 19 is provided with a lever 20 provided so as to be swingable, and a pressing rod 21 that is pressed by the lever 20 and presses the permanent magnet 5 ″ on the pedestal 19. Further, the rear end portion 6 b of the capsule 2 is made of a flexible material, and is easily deformed when an external force F is applied, so that the external force F can be transmitted to the lever 20. In the figure, reference numeral 20 a is a force point for applying an external force F to the lever 20.

The pedestal 19 includes two suction surfaces 19a and 19b having a step, and each suction surface 19a and 19b is made of a magnetic material to attract the permanent magnet 5 ″.
The pressing rod 21 is provided so as to be able to protrude and retract through one suction surface 19 a of the pedestal 19.

  According to the capsule endoscope 1 ″ according to the present embodiment configured as described above, first, the magnetic pole of the permanent magnet 5 ″ is orthogonal to the longitudinal axis R of the capsule 2 as shown in FIG. Set to the progress mode arranged in the direction. Then, the capsule endoscope 1 ″ is rotated around the longitudinal axis R by the operation of the guidance system 30 and is advanced in the direction along the longitudinal axis R.

  When the capsule endoscope 1 ″ reaches the target position, the rear end portion 6b of the capsule 2 is pressed against the body cavity inner wall surface B. The capsule endoscope 1 is operated by operating the guidance system 30. 1 ″ is rotated backward about the longitudinal axis R and advanced toward the rear end 6b side, or a capsule-type endoscope 1 ″ in the body is magnetically attracted by bringing a strong magnet close to the body of the subject A There is a method of attracting by force.

  When the rear end portion 6b of the capsule 2 is pressed against the body cavity inner wall surface B, the rear end portion 6b of the capsule 2 is deformed, the external force F acts on the force point 20a, and the lever 20 swings. Thereby, the lever 20 presses the pressing rod 21, and the tip of the pressing rod 21 protrudes from the attracting surface 19a, and as shown in FIG. 19B, the permanent magnet 5 attracted and held on the attracting surface 19a. ″ Is rotated away from the suction surface 19a.

  Since the pedestal 19 is provided with a step, when the permanent magnet 5 ″ rotates, another magnetic pole different from the magnetic pole attracted to the attracting surface 19a approaches the other attracting surface 19b and approaches a predetermined distance. Then, as shown in FIG. 19 (c), the magnetic attracting force attracts the attracting surface 19b, thereby rotating the permanent magnet 5 ″ by 90 °. In this state, the permanent magnet 5 ″ has its magnetic pole arranged in the direction along the longitudinal axis R of the capsule 2, and the induction mode is switched to the direction change mode.

  Therefore, thereafter, the capsule endoscope 1 ″ can direct the front end portion 6a in a desired direction by the action of the external magnetic field M, and an image of the inner wall surface of the body cavity around the target position can be freely set. Then, after the observation around the target position is completed, it is naturally discharged by the peristaltic movement of the body cavity or the like.

  In the present embodiment, the switching of the guidance mode is limited to only one time from the traveling mode to the direction changing mode, but conversely, the switching from the direction changing mode to the traveling mode may be performed. Further, as shown in FIG. 20, by providing a second pressing rod 22 that is pressed by the permanent magnet 5 ″ when switched to the direction changing mode on the attracting surface 19b side, the traveling mode and the direction changing are performed. It is good also as making a mode mutually switchable many times.

  In each of the above embodiments, the induction mode is switched by rotating the permanent magnets 5, 5 ′, 5 ″ by 90 °. Instead, the direction and the longitudinal direction along the longitudinal axis R of the capsule 2 are changed. An electromagnet (not shown) capable of setting magnetic poles in both directions orthogonal to the axis R is arranged in the capsule 2 and a magnetic pole switching device (not shown) for switching the magnetic poles according to an external command signal is mounted. Also good.

In each of the above embodiments, the three-axis Helmholtz coil unit 71 is cited as the magnetic field generator. However, the magnetic field generator is not limited to the Helmholtz type, and a plurality of electromagnets are arranged in a plane and above the electromagnet. A planar magnetic device that generates a substantially uniform magnetic field may be employed. Also, other types of magnetic devices may be used.
Furthermore, in each of the above embodiments, the method using an induced magnetic field as a position detection system has been described. However, the present invention is not limited to this method, and any technique that can detect at least the direction of the longitudinal axis R of the capsule endoscope. Any method can be employed.

1 is a longitudinal sectional view schematically showing a configuration of a capsule endoscope according to a first embodiment of the present invention. It is a perspective view explaining switching of the guidance mode of the capsule endoscope of FIG. 1, (a) shows a traveling mode, (b) shows a direction change mode, respectively. It is the schematic which shows the guidance system of the capsule endoscope which concerns on the 1st Embodiment of this invention. It is a perspective view which shows the guidance system of FIG. It is a longitudinal cross-sectional view which shows the guidance system of FIG. It is a graph which shows the frequency characteristic of the resonance circuit of the capsule endoscope of FIG. It is a longitudinal cross-sectional view which shows partially the 1st modification of the capsule type endoscope of FIG. It is an expanded sectional view explaining the click mechanism of the capsule endoscope of FIG. It is a perspective view which shows the 2nd modification of the capsule endoscope of FIG. FIG. 10 is a longitudinal sectional view partially showing the capsule endoscope of FIG. 9. It is a longitudinal cross-sectional view which shows the modification of the capsule type endoscope of FIG. It is a perspective view which shows the 3rd modification of the capsule endoscope of FIG. It is a perspective view which shows the 4th modification of the capsule endoscope of FIG. It is a longitudinal cross-sectional view which shows operation | movement of the 5th modification of the capsule endoscope of FIG. It is a partial longitudinal cross-sectional view which shows operation | movement of the capsule type endoscope which concerns on the 2nd Embodiment of this invention. FIG. 16 is a longitudinal sectional view partially showing a first modification of the capsule endoscope of FIG. 15. FIG. 16 is a longitudinal sectional view partially showing a second modification of the capsule endoscope of FIG. 15. FIG. 16 is a longitudinal sectional view partially showing a third modification of the capsule endoscope of FIG. 15. It is a partial longitudinal cross-sectional view which shows operation | movement of the capsule type endoscope which concerns on the 3rd Embodiment of this invention. FIG. 20 is a longitudinal sectional view showing a modification of the capsule endoscope of FIG.

Explanation of symbols

A Subject (subject)
M external magnetic field R longitudinal axis 1,1 ', 1 "capsule endoscope (capsule medical device)
2 capsules 5,5 ', 5 "permanent magnet
5a Recess (engagement member)
7 Spiral part (spiral mechanism, propulsion mechanism)
12 Rotating shaft (fixing means)
13 Stopper (Fixing means)
14 Click mechanism (engagement member: fixing means)
14a Ball (engagement member)
14a 'shaft (engaging member)
15 Clutch device (fixing means)
16 motor (magnetic pole direction switching device)
17 Electromagnet 30 Guidance System 50A Position Detection Device (Capsule Direction Detection Device)
71 3-axis Helmholtz coil unit (magnetic field generator)
73 Magnetic field control device

Claims (11)

A capsule medical device that is introduced into the body of a subject and guided by an external magnetic field,
A substantially cylindrical capsule;
A propulsion mechanism that converts rotational movement about the longitudinal axis of the capsule into propulsive movement along the longitudinal axis;
A magnet housed in the capsule and provided so that the direction of the magnetic pole can be switched between a direction along the longitudinal axis and a direction intersecting the longitudinal axis;
A capsule medical device comprising: a fixing means for fixing the magnet to the capsule in each state in which the direction of the magnetic pole is switched. A capsule medical device that is introduced into the body of a subject and guided by an external magnetic field,
A substantially cylindrical capsule;
The direction accommodated in the capsule and the direction of the magnetic pole along the longitudinal axis and the direction crossing the direction A magnet that can be switched between and
Fixing means for fixing the magnet to the capsule in each state in which the direction of the magnetic pole is switched A capsule medical device.   The capsule medical device according to claim 1, wherein the propulsion mechanism is a spiral mechanism provided on an outer peripheral surface of the capsule. The magnet comprises a permanent magnet;
Said fixing means includes a position toward the direction along the pole to the longitudinal axis, one of claims 1 to 3 comprising a engaging member for engaging the magnet and a position toward the direction intersecting thereto The capsule medical device according to 1. The magnet comprises a permanent magnet;
Said fixing means, according to any of the position for the direction along the pole longitudinal axis, claim 1 made of a magnetic material that adsorbs to the magnet and a position toward the direction crossing to claim 3 Capsule medical device. The capsule medical device according to any one of claims 1 to 5, further comprising a magnetic pole direction switching device that switches a magnetic pole direction of the magnet. The magnet comprises a permanent magnet;
The fixing means comprises an electromagnet that is attracted to the magnet at a position where the magnetic pole is oriented in a direction along the longitudinal axis and a position oriented in a direction crossing the magnetic pole;
The capsule medical device according to claim 6 , wherein the magnetic pole direction switching device includes a magnetic pole switching device that switches a magnetic pole of the electromagnet. The magnet comprises a permanent magnet;
The capsule medical device according to claim 6 , wherein the magnetic pole direction switching device includes a motor that swings the magnet around an axis along the radial direction of the capsule. The magnet comprises an electromagnet;
The capsule medical device according to claim 6 , wherein the fixing unit and the magnetic pole direction switching device include a magnetic pole switching device that switches and holds a magnetic pole of the electromagnet. The capsule medical device according to any one of claims 1 to 5 ,
A magnetic field generator arranged outside the operating range of the capsule medical device and generating an external magnetic field that acts on the magnet in the capsule medical device;
A capsule medical device guidance system comprising: a magnetic field control device that controls an external magnetic field applied to the magnet by the magnetic field generation device. A capsule direction detection device for detecting the direction of the capsule medical device;
Wherein the magnetic field control device, wherein depending on the direction of the capsule direction detecting device by the detected capsule medical apparatus, the capsule medical device according to claim 1 0 of controlling the direction of the external magnetic field at the location of the capsule medical device Induction system.

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