KR20040007181A - Remote driving system using magnetic field for wireless telemetry capsule in the body - Google Patents

Abstract

PURPOSE: A remote magnetic driving device of an internal wireless telemetry capsule is provided to perform easily a diagnosing operation and a curing operation by using a capsule inserted into the human body and an external part for controlling the capsule. CONSTITUTION: A remote magnetic driving device of an internal wireless telemetry capsule includes an internal capsule(210) and an external part(220). A permanent magnet is installed in the inside of the internal capsule(210). A position of internal capsule(210) is changed according to the intensity of the external magnetic field. The external part(220) detects a position of the internal capsule(210) and controls the intensity of the external magnetic field to move the position of the internal capsule(210). The internal capsule(210) is formed with the permanent magnet and a function portion for diagnosing operation and a prescribing operation.

Description

Remote driving system using magnetic field for wireless telemetry capsule in the body}

Recently, a wireless transmission capsule with a tiny camera inserted into the esophagus by the media has been introduced. The capsule, which was developed under the name of M2A by Israel's 'Given Imaging' company, is 11mm thick and 2.6cm long, and can be used for observation of the small intestine because it can transmit images for 8 hours due to battery life. Norika, a Japanese company, has announced that they have developed a similar wireless endoscope capsule.

In the near future, smaller microcapsules are expected to be developed to move around the blood vessels or endocrine system to treat and diagnose diseases. However, one of the fatal problems with the technology of the capsule in the body is that the capsule does not move by itself. In the case of the recent M2A capsule, only the periphery of the intestinal periphery moves downward and the image taken during the passage from the esophagus to the anus is transmitted only at regular intervals. If you want to move the capsule, you need mechanical mechanisms such as a battery to supply energy for movement and a motor to move. Not only is it difficult to put all of them in a small capsule, but even if it is hard to put it, the driving time is short because the volume of the battery is extremely limited. There is no choice but to. Microcapsules that are placed in blood vessels or endocrine tubes are more power-prone because of their small size. Therefore, in the case of microcapsules that are placed in blood vessels or endocrine tubes, the only way to reach the capsule is to move the heart along the flow of pumped blood.

1 illustrates a conventional telemetry capsule device for diagnosis by a control signal to an electromagnetic wave. In the telemetry device that transmits the biological signal or the image information obtained from the measuring unit 113 to the outside of the body using the transmitter 111, the position is generated by the operation of the wobble or squeeze in accordance with the position information received from the outside It is characterized in that it consists of a capsule 110 that can move and the outer body 120 for detecting a position signal generated inside the capsule to generate a control signal for moving to the desired position. At this time, the capsule is for receiving the signal transmitted from the outside in the capsule receiving unit 112, for transmitting the control signal for controlling the current position according to the position information included in the received signal to the motion movement generating unit 114 It consists of a control part 115 and a power supply part 116. In addition, the body part is an extracorporeal receiver 121 for receiving the acquired image signal and the position signal transmitted from the capsule, a position detector 122 for detecting the position of the capsule by the received position information, the detection position of the position detector And a control unit 123 for generating a control signal for movement of the capsule by calculating a difference between the desired position and a control signal transmitter 124 for transmitting the generated control signal to the capsule. In this method, it is difficult to reduce the size of the capsule due to the battery volume, and it is impossible to move the body for a long time.

In order to greatly reduce the volume of the battery when supplying the power consumed in the capsule inside the body, a method of applying strong electromagnetic waves from the outside toward the capsule and placing a coil on the capsule to rectify the electromotive force induced in the coil may be proposed. However, in this method, since the volume of the capsule is very small, the coil for obtaining the induced electromotive force cannot be enlarged, and the energy density of the electromagnetic wave that is externally supplied to the living body must be very large so that the capsule can absorb the required energy. In this case, the intensity of electromagnetic waves applied through living tissue is so great that it exceeds the FDA's tolerance. Therefore, it is impossible to supply power for moving the capsule through external electromagnetic waves.

In the case of microcapsules to be placed in blood vessels or endocrine tubes, recent MEMS technology is advanced. Even if it is hard, it is difficult to implement a motor or a driving mechanism, and it is more difficult to secure a space for a battery. For this reason, it is most desirable to devise a driving method for moving a capsule arbitrarily introduced into the body from the outside without giving a complex mechanism or a battery for moving inside the capsule and applying energy to the body capsule with electromagnetic energy.

In this proposal, a small permanent magnet is put in a capsule to be injected into the body, and by controlling the strength and NS polarity of the electromagnet generating strong static fields in the X, Y, and Z directions, the direction and speed of the capsule can be freely controlled. Is to allow remote control. In addition, in order to facilitate the initial movement of the capsule encapsulated in biological tissues such as organs and blood vessels in the body, a method of applying a slow alternating magnetic field of less than 10 Hz to minimize the generation of induced electromotive force to the living body and external for a short time Is proposed to cause the centrifugal force to dissipate a therapeutic agent such as drugs inside the capsule by applying a fast rotating magnetic field to the outside of the capsule, and supply a short time of the external alternating magnetic field resonating to the size of the microcapsule shell made of magnetic material. Proposal of ejecting the drug out of the capsule through the burst by.

1 is a block diagram of a conventional wireless capsule device.

2 is a schematic diagram of a wireless capsule magnetic field remotely operated device of the present invention, b is an internal view of a therapeutic microcapsule, and c is an internal view of a diagnostic and therapeutic capsule.

Figure 3 is an embodiment of a magnetic field remote drive device of the wireless capsule according to the present invention.

4 is a block diagram of a device for moving the capsule in the z-axis direction and b is a cross-sectional view of the drive device in the z-axis direction.

5 a and b are schematic diagrams of a device for moving a capsule on the x and y axes.

6A and 6B show an embodiment in which the electromagnet coil for the z-axis is wound to the outside of the assembly ring.

7 is a configuration diagram of a position detector for position control.

8 a and b are alternating magnetic field control signals for position escape of capsules.

9 is a block diagram of a non-destructive therapeutic capsule.

10 is a structural diagram of the centrifugal force destruction type therapeutic microcapsules.

Figure 2 shows a magnetic field remote drive of the in-body wireless diagnostic capsule of the present invention. This is a wireless capsule device which is inserted into the body and transmits the detected image or biological signal to the outside of the body, including a permanent magnet inside the capsule 210 that can move the position according to the strength of the external magnetic field and the capsule Characterized in that the outer portion 220 for detecting the position to adjust the intensity of the external magnetic field required for moving the position.

At this time, the capsule has a permanent magnet 211 and a functional part 212 to obtain a force for the position movement by working with the magnetic field generated in the outside of the body. According to the configuration, the functional unit is divided into a form capable of simultaneously inputting a biosignal and image measurement. The functional part of the micro telemetry capsule for biometric measurement may include a medicine for treatment or a micro drill to pierce the blood vessel in the case of the microcapsules injected into the blood vessel and endocrine tube as shown in FIG. 2- (b). . 2- (c) In the case of biodiagnosis and treatment, the internal transceiver unit 213 for transmitting information to the body and receiving external control signals from the internal body position and supplying power for driving the information acquisition unit and the transceiver unit Characterized in that consisting of a power supply unit 215 and a storage tank for treatment,

In addition, the extracorporeal portion of the biodiagnostic capsule is an in vitro transceiving unit 221 for receiving the information obtained from the capsule and transmitting a signal for function control into the body, and detecting the location of the current capsule using the received signal. A position detecting unit 224 for comparing the detected position with a desired position and calculating position information to be moved, and a position control unit 221 for transmitting necessary control signals to the magnetic field generating unit according to the calculated position information. And magnetic field generators 225-1 and 225-2 for generating a magnetic field necessary for the movement of the capsule according to the position control signal.

Figure 3 shows an embodiment of a magnetic field remote drive capsule system according to the present invention, showing the overall system configuration for moving the capsule in the desired direction by controlling the strength and direction of the magnetic field from the outside of the body. (1) is a table plate for the patient to lie down and is driven to move back and forth in the direction of the arrow. (2) is an assembly ring containing an electromagnet for moving the capsule by magnetic force, x-axis (the direction in which the arm extends the body), y-axis (the belly and dorsal side of the body), z-axis (head to leg) direction An electromagnet that generates magnetic lines of force is built in. The assembly ring has no mechanical movement and is fixed in place, but the electromagnetic coils are energized with a current corresponding to the output signal provided by the position control circuit so that a strong magnetic field can be generated to move the capsule to the desired coordinates. Is provided. As the electromagnets, superconducting magnets and phase conducting magnets may be used. Thus, using the table and the assembly ring, the table is driven in conjunction with the movement of the table back and forth in the direction of the arrow so that the capsule can be located at the center of the control magnetic field of the electromagnet contained in the capsule (3). It is a leg for supporting the table, on which a guide rail (4) is mounted so that the table can move in the z-axis direction, and a table plate is mounted on the rail. (5) includes a drive motor and a reduction gear for driving the table. The control power driver 7 is responsible for converting a large current to drive an electromagnet from a signal generated from the control computer 8 and receiving a table control signal to supply power for driving the table. When the coordinate signal detected by the capsule position detection system 9 is input, the control computer 7 sends an input signal to the control power driver 8 so that the drive current of the precise electromagnet necessary for position control can be calculated and supplied to the assembly ring. . As a method for detecting the position of the capsule, it is possible to use the method for measuring the position of the in-place telemetry capsule applied in Korea in early May 2002 (application number: 02-27334). Obtain the position after image processing by using a fluoro-scopic X-ray system or digital X-ray device, or install a weak electromagnetic wave oscillator inside the capsule, and generate the electromagnetic wave more than 3 points outside the body The method of calculating the position by measuring in and a small amount of current flows to the electrode installed in the capsule shell and detect it using an electrode from the outside and then calculate the position.

4a and 4b show the structure of the device for moving the capsule in the z-axis direction. A cylindrical solenoid coil wound in the z axis direction is arranged to move the capsule in the z axis direction. The shape of the current figure shows that the permanent magnet is offset slightly to the right of the center of the solenoid coil, in which case the magnet is forced from the right side of the z axis to the left. Actually, the force required to pass a capsule 1cm long and 3cm long inside a soft tissue tube such as organs or blood vessels inside the body is expected to be less than 1000 dyne. If the permanent magnet inside the capsule with the strength of m (Wb) is located, the force F generated between the electromagnet coil and the magnet is the strength of the magnetic field produced by the coil and the current flowing through the coil is I (A).

Where the magnetic field strength H is

Is given by The strength of the permanent magnet in the capsule is 1000 Gauss, and when the electromagnet with a radius of 50 cm uses an air core coil of N = 5000 without using cores such as iron cores, the specific permeability of air is about 1, which is required at this time of about 180 (A) It is necessary to manufacture a variable power supply and an electromagnet capable of supplying such a current, and both superconducting and phase conducting methods can be sufficiently implemented as domestic technologies. When moving magnets in the body, the force of the permanent magnet in the capsule is also related to the magnitude of the current passing through the electromagnet and the distance and angle between the electromagnet ring and the capsule. Position control is performed by passing a current through the electromagnet. In order to ensure proper distance between the capsule and the electromagnet coil, the patient's lying table in the + z and -z axes can be moved by computer control.

5 (a) and 5 (b) show the polarity and current application of the electromagnets when the capsules are moved along the X and Y axes, respectively. In order to move the capsule in the X-axis direction, there is no need to apply a current to the coil in the Y-axis direction. And when moving in the Y-axis direction as shown in (b) does not apply the current in the X-axis direction.

In the figure, the electromagnetic coil for the Z axis is wound around the outside of the assembly ring and the X and Y coils are located inside the coil, but the structure of the positioning system occupies a volume of x-ray tube and x-ray. In the case of using a shape that does not occupy a volume such as a position measuring device using electromagnetic waves and skin-attached electrodes without using an image detecting plate, the Z-axis coil may be wound around the innermost part of the assembly ring.

FIG. 6 illustrates an embodiment in which the z-axis electromagnet coil is wound to the outside of the assembly ring. In this case, an x-ray tube and an x-ray image detection plate were used to measure the position of the patient capsule. 6 (a) and 6 (b), the person with the capsule lies in the center of the assembly ring, and two x-ray tubes at an angle of 90 degrees fire the beam toward the person and then the other side after the body penetration. After reaching the digital x-ray detection plate for image detection located at, the received positional information of the capsule is obtained after image processing by a computer having the shape recognition function of the capsule. If a strong driving magnetic field is generated from the solenoid coil during capsule position shooting, the electron beam driving path inside the x-ray tube may be out of focus, so the capsule driving signal and position measurement should be performed alternately. In the case of using the detection method, the position measurement and the position movement may be performed simultaneously.

As such, the capsule can be moved while measuring the position of the capsule in the X, Y, and Z directions in the body. In order to accurately control the position of the capsule to a desired point by an external observer, a real time position as shown in the block diagram of FIG. Position feedback control is needed. That is, when a doctor or a practitioner inputs the position coordinates (X, Y, Z) desired for observation or treatment, an error with the position (X ', Y', Z ') measured by the position detecting device detecting the current position of the capsule Calculate the components ((X-X '), (Y-Y'), (Z-Z ')) and output the servo motor output for driving the patient table for movement in the controller, the magnitude and direction of the current to flow to the electromagnet coil, The output of the angle control servo is determined and supplied to each of the three control objects. This results in a new capsule position and this value is fed back into the feedback input, reducing the error and ultimately the desired position control by the external magnet. The possibility of precisely controlling the position of the capsule by the position feedback control by the external magnetic field does not allow the iron ball, which is about 2-3 cm in diameter, to fall off the ground and stick to the magnet above. You can be sure that you just make the exhibits that stop in the space and show them to the audience.

5 and 6 not only move the capsule with a permanent magnet inside the patient to any position in the body but also generate a rotating magnetic field, as shown in (a) and (b) of FIG. The electric current is allowed to flow in order to sequentially rotate the poles of the four electromagnets arranged in a circle. This means that the current is controlled to play the same role as the field of the AC motor. The frequency of the rotating magnetic field is given by the frequency of alternating current applied to the field, f and the number of poles of the field, as follows. .

Given the four poles for the given figure, the speed of the rotating magnetic field per minute can be obtained at a high speed of 12000 rpm when the frequency is 400 Hz. In addition, a frequency of 20 Hz yields 600 rpm, or 10 rotating magnetic fields per second.

If the capsule is jammed or stuck due to protrusions or foreign objects of the body tissue, even if the external static magnetic field is very strong, it may not move, and the initial movement of the patient's intestine or blood vessels is required. However, it is inconvenient for the observer to provide an initial exercise to communicate by touching the area where the capsule is located. Therefore, by applying an alternating magnetic field of less than 10 Hz for a short time as shown in FIG. 8, the capsule vibrates back and forth or back and forth left and right to provide an initial movement.

When the microcapsules are put into the digestive tract and the blood vessels or endocrine system for therapeutic purposes, the positional movement to pull the capsule to the correct target insertion position is essential, but the microcapsules that are put into the vessels and the endocrine tract, or somewhat into the digestive tract In the case of bulky capsules, it is necessary to release the therapeutic drug contained in the capsule out of the capsule.

9 shows a method for implementing a non-destructive capsule for releasing the drug of the capsule to the outside by external control. Figure 9a shows the installation of a micro permanent magnet in the shape of connecting two pieces of "b" in the capsule case inside. Since these permanent magnets are present in the capsule, it is possible to control the movement to the target position by the DC magnetic field for position control in the assembly ring outside the body. The lower of these two "b" permanent magnets is made slightly larger in mass than the upper one. And the lower "b" permanent magnet is aspirated and attached to the soft iron structure of the capsule shell, while the upper "b" permanent magnet is floating in the space at intervals from the inner surface of the capsule.

9B shows that the N pole of the permanent magnet is attached to the inner wall of the capsule in the stationary capsule and the S pole is floating in the space, so that the N pole portion attached to the wall is blocking the drug release hole drilled in the case directly below. to be.

If the four electromagnets of the assembly ring outside the body form a rotor that rotates hundreds to tens of thousands of times per second, the permanent magnets in the capsule will be like a rotor of a synchronous motor or a stepping motor. Because the capsule rotates along the rotating magnetic field. When a rotating magnetic field occurs in the ring outside the body, the capsule rotates as shown in Fig. (C), and the S pole is attached to the wall as the whole magnet is inverted obliquely by the centrifugal force of the “b” shaped ultra-small permanent magnet. Then, the S pole of the lower "B" micro permanent magnet falls off the wall and the blocked holes are opened so that the drug inside is also released to the outside in the direction of the arrow due to the centrifugal force. The alternating magnetic field for initial exercise or the rotating magnetic field for drug release is exposed to very short periods of time, less than 1-2 seconds, thereby preventing the risk to the human body.

Figure 10 shows the principle and configuration of the breakable microcapsules of less than 1000 ㎛ size used to inject the drug in the blood vessels and endocrine vessels. The therapeutic agent enters the capsule shaped like a back hole, and the outer shell of the capsule is composed of small permanent magnets woven into contact with each other. The microcapsules are rotated on the same principle as in the case of the rotating magnetic field generating device as shown in FIG. 6 and the capsule as shown in FIG. When the microcapsule rotates at high speed, the capsule is destroyed by centrifugal force, and the drug stored therein is released into blood vessels and tissues to achieve a predetermined therapeutic purpose. The intrinsic rotational speed of a microcapsule is given as a function of the magnetic domain size and mass of the magnetic debris constituting the capsule, and the strength of the permanent magnets. Occurs and capsules and harm are triggered to release the drug. After the breakdown of the capsule, the debris are all permanent magnets smaller than the size of the small capsule. Therefore, the debris can be gathered to a specific blood vessel or skin by collecting a strong static magnetic field.

In the present invention, all the energy required to move the microcapsules into the body is given in the form of a static magnetic field harmless to the human body from the outside, not inside the capsule, so that the size of the capsule is not only small but also safe. It is superior to any conventional device of any type of movement, powered by a compact machine and powered by batteries. In addition, even if the capsule stays in the body for a long time for a long time to move a long distance is not a problem in the supply of energy required for exercise at all, it allows a stable treatment and procedures for a long time. In addition, in the case of microcapsules that are precisely moved to the capsule as well as injected into the blood vessel or endocrine tube, the drug can be injected from the stomach and discharged from the desired position, so that the ultra-compact wireless endoscope by telemetry, treatment of various vascular diseases, chemotherapy, It can be widely used for hormone therapy.

Claims (10)

Including a permanent magnet therein, the in vivo insertion capsule which can move the position according to the strength of the external magnetic field and the external part to detect the position of the capsule to adjust the strength of the external magnetic field required for the position movement Magnetic field remote drive of wireless telemetry capsule in the body. The method according to claim 1, the in vivo insertion capsule is responsible for the treatment function such as the permanent magnet for obtaining a force for position movement by working with the magnetic field generated in vitro, the diagnosis by the acquisition of biometric information at the inserted body position and drug administration Magnetic field remote drive of the wireless telemetry capsule in the body, characterized in that consisting of a functional unit. The method of claim 2, wherein the inner portion includes a tank for storing the therapeutic agent in the diagnosis and disclosure, as well as bio-diagnostic information such as electrocardiogram, gastrointestinal tract, pH, endoscopy image, etc. The apparatus of claim 1, wherein the extracorporeal unit receives an biological information transmitted from the capsule and transmits a signal for controlling the function of the capsule, a position detecting unit for detecting a position of the current capsule using the received signal, and detection. A control unit for calculating the position information to be moved by comparing the desired position by feeding back the real-time position in real time, a position control unit for transmitting a necessary control signal according to the calculated position information to the magnetic field generating unit, and the position control signal Magnetic field remote drive of the wireless telemetry capsule in the body, characterized in that consisting of a magnetic field generating unit for generating a magnetic field required for the movement of the capsule. The apparatus of claim 4, wherein the magnetic field generating unit generates an alternating magnetic field for initial driving so that the capsule can be separated from the fixed position. The apparatus of claim 4, wherein the magnetic field generator comprises an electromagnet made of a superconducting magnet or a phase conducting magnet. The apparatus of claim 4, wherein the magnetic field generating unit generates a rotating magnetic field so that the permanent magnet of the capsule is separated from the case by centrifugal force to inject drugs. The apparatus of claim 4, wherein the position detector comprises an x-ray tube and an x-ray image detection plate. Two 'L' shaped magnets with different masses are engaged and connected, and the heavy side blocks the drug exit of the case and stops the drug outflow when it stops. Non-destructive therapeutic capsule consisting of a case for fixing the permanent magnet is made of a soft iron material at the same time the opening for the injection of the drug, the permanent magnet to create a gap Consists of a circular or elliptical shape and can be destroyed by an external rotor field resonating with the strength of the synthetic magnetic field of the magnetic domain.Fragments are induced by the external static field and then discharged out of the body by a suction device such as a syringe. Destroyable therapeutic capsule, characterized in that the ultra-small permanent magnet pieces and the microcapsules contained inside the capsule is broken out to the outside as a therapeutic agent for use in diagnosis and treatment.