The present invention relates to a magnetic guiding medical system that magnetically guides a medical apparatus which is inserted in the living body.
U.S. Patent Publication No. 3358676 discloses a magnetic propulsion apparatus for guiding through the body cavity or the like, in which nine electromagnets are disposed on the plane and further electromagnets are disposed on the plane facing each other.
Further, PCT WO 02/49705 description discloses a generating apparatus of the three-dimensional magnetic field on the top of two parallel pairs of electromagnets by orthogonally laminating the two pairs of electromagnets and disposing one electromagnet to surround one of the two pairs.
In the conventional example, with the structure in which the electromagnets are disposed on the plane and the three-dimensional magnetic field is generated on the top thereof, the space for ideally generating the magnetic field is extremely limited.
Therefore, in the magnetic guiding medical system, upon guiding, by the magnetic generating device, the medical apparatus having an insertion unit into the body and a permanent magnet in the insertion unit into the body, there is such a problem that the area for guiding the insertion unit is not sufficiently ensured and the precision of the generated magnetic field at the position for generating the magnetic field deteriorates.
According to the present invention, a magnetic guiding medical system comprises:
a medical apparatus having an insertion unit that is inserted in the body cavity of the living body;
a position/posture detecting unit that detects at least one of the position and the posture of the insertion unit;
a magnetic field generating unit having at least three electromagnets that are axial-symmetrically arranged on the substantially plane and have the magnetizing directions in the orthogonal direction of the plane;
a magnetic field control unit that controls the magnetic field generated by the magnetic field generating unit;
a position/posture varying unit that changes a relative position/posture between the magnetic field generating unit and the insertion unit in accordance with information on the position and the posture of the insertion unit obtained by the position/posture detecting unit; and
a magnetic field operated unit arranged to the insertion unit;
wherein the magnetic field generated by the magnetic field generating unit operates on the magnetic field operated unit, thereby guiding the medical apparatus.
With the above-mentioned structure, the changing operation of a relative position/posture between the magnetic generating unit and the insertion unit is controlled so that the position of the insertion unit of the medical apparatus is recognized and the optimum magnetic field is generated at the recognized position, thereby setting a wide controllable region in the living body.
Hereinbelow, embodiments of the present invention will be described with reference to the drawings.
A first embodiment of the present invention will be described with reference to FIGS. 1 to 29.
Referring to
Referring to
The receiving antenna unit 73 and the magnetic field generating unit 2 are held movably in the X axial direction and the Y axial direction by the planar moving mechanism 77. The receiving antenna unit 73 and the magnetic field generating unit 2 may be accommodated in a common casing.
The planar moving mechanism unit 74 comprises: the X axial direction moving-stage 77A; the Y axial direction moving-stage 77B; and an in-planar position control unit 78 which controls the positions on the plane of the X axial direction moving-stage 77A and of the Y axial direction moving-stage 77B.
As will be described later, according to the first embodiment, a magnetic field generating region controllable by the magnetic field by the single magnetic field generating unit 2 is extremely limited. However, the planar moving mechanism 77 moves the magnetic field generating unit 2, thereby widening the guidable region.
The control operation of current flowing to electromagnet units 3 to 5 forming the magnetic field generating unit 2 generates the optimum magnetic field near the capsule medical apparatus 72, which is the guiding and control target, inserted in the patient 23 and further widens the guidable region.
The in-planar position control unit 78 is connected to an external control unit 76 via a signal cable 79.
Referring to
Referring to
A control unit 85 controls the driving operation of the LEDs 83 and the image pickup device 84. The control unit 85 performs the signal processing of the signal picked-up by the image pickup device 84. For example, the control unit 85 compresses the signal, then modulates the signal, and sends the signal by wireless manner via an antenna 86. The container 81 includes: a battery 87 for supplying the power to the control unit 85; and a magnet 88, serving as magnetic-field operated means (magnetic-field operated unit), which operates on the magnetic field generated by the magnetic field generating unit 2 near the center of the container 81 in the longitudinal direction thereof.
Outside the container 81, a spiral structure 89 is arranged to be spirally projected from a cylindrical outer surface of the container 81. The capsule medical apparatus 72 is efficiently propelled by rotating the spiral structure 89 in contact with the inner wall of the body cavity.
The receiving antenna unit 73 shown in
Referring to
The signal processing unit 91 sends, to a position detecting unit (position/posture detecting unit) 94, the signal received by the receiving antenna unit 73 or an antenna strength signal, serving as the strength of the signals received by the receiving antenna unit 73.
The position detecting unit 94 detects, based on the antenna strength signal, the three-dimensional position and the posture of the capsule medical apparatus 72. In this case, the receiving antenna unit 73 shown in
In this case, the antenna 73e, serving as one reference, is arranged on a central axis O of the magnetic field generating unit 2, and the plurality of antennas 73a to 77d and 73f to 73i are arranged therearound.
The plurality of antennas 73a to 73i receive the signals sent from the antenna 86 of the capsule medical apparatus 72, and the position of the capsule medical apparatus 72 is detected based on the strength of electromagnetic field (antenna strength signal).
That is, the strength of electromagnetic field of the receiving signal using the positions of the antenna 73j (j=a to i), as the reference, is proportional to the square of the distance. Then, the three-dimensional position of the capsule medical apparatus 72 is calculated by using the trigonometry. Further, the direction of the capsule medical apparatus 72, e.g., the direction of the magnet 88 is detected. An antenna for detecting the image signal from the capsule medical apparatus 72 may be formed, independently of an antenna for detecting the position (and posture).
According to the first embodiment, the position of the capsule medical apparatus 72 is detected by using the electromagnetic field, thereby calculating the position with high precision without interference with the guiding magnetic field. Further, since the electromagnetic field is used to send the image data, both the functions are shared and the efficient use is possible.
The positional information and the posture information (direction information) of the capsule medical apparatus 72 detected by the position detecting unit 94 are sent to the planar moving mechanism unit 74 and the magnetic field control unit 95 as shown in
The in-planar position control unit 78 of the planar moving mechanism unit 74 controls the two-dimensional position of the planar moving mechanism 77 based on the positional information. That is, the in-planar position control unit 78 controls the planar moving mechanism 77 so that the center of the magnetic field generating unit 2 matches the position on the X coordinate and Y coordinate of the positional information detected by the position detecting unit 94. The generating direction of the rotating magnetic field in the case of applying the rotating magnetic field is controlled based on the posture information of the capsule medical apparatus 72. As mentioned above, the position detecting unit 94 and the in-planar position control unit 78 form a relative-position detecting mechanism which obtains the positional relationship (relative position) between the capsule medical apparatus 72 and the magnetic field generating unit 2. The in-planar position control unit 78 controls the position of the magnetic field generating unit 2 based on the relative position obtained by the relative-position detecting mechanism.
In order for the magnetic field generating unit 2 to generate the magnetic field in the arbitrary direction, the magnetic field control unit 95 comprises: an electromagnet current control unit (abbreviated to a current control unit) 96 for controlling a value of current (level of magnetic field) flowing to electromagnets; and a generated magnetic field storing unit 97 which stores the direction and level of the generated magnetic field. The magnetic field generating unit 2 comprises: a first electromagnet unit having electromagnets 4a and 4b, a second electromagnet unit having electromagnets 3a and 3b, and a third electromagnet unit 5 having the electromagnet 5.
The receiving antenna unit 73 is two-dimensionally moved together with the magnetic field generating unit 2. That is, generally, the planar moving mechanism 77 moves and sets the receiving antenna unit 73 at the position of the antenna 73e, as the reference, so as to maximize the receiving strength.
The approximation is possible when the capsule medical apparatus 72 exists just on the top of the antenna 73e having the largest receiving strength. Thus, since the capsule medical apparatus 72 always exists on the top of the antenna 73e, the image is sent stably and efficiently and the precision for detecting the position is improved. In addition, advantageously, the number of antennas is reduced and the algorithm for controlling the position of the magnetic field generating unit is easy.
The receiving antenna unit 73 is arranged on the top of the magnetic field generating unit 2 as shown in
Referring to
Referring to
Further, the instruction/operation unit 10 comprises a keyboard 100 for setting the magnetic field which sets the direction and the level of the generated magnetic field in accordance with the instructing operation via the magnetic field control unit 95.
Referring to
Further, a user controls the generated magnetic field by operating the instruction/operation unit 10 connected to the current control unit 96.
According to the first embodiment, referring to
The electromagnets 3a and 3b, forming a pair, have the matching characteristics. Preferably, the electromagnets 4a and 4b, forming a pair, have the matching characteristics. Preferably, the electromagnet 3a (3b) and the electromagnet 4a (4b) have the matching characteristics.
In other words, in the case of manufacturing the magnetic field generating unit 2 according to the first embodiment, the electromagnets 3a, 3b, 4a, and 4b, forming the pairs, may have the symmetric arrangement of the same electromagnets. Advantageously, the costs are reduced.
Referring to
Referring to
Referring to
As shown by the length of an arrow in
Referring to
The operation (of the keyboard 100) of the instruction/operation unit 10 shown in
As mentioned above, according to the first embodiment, the three sets of the electromagnets 3a and 3b, 4a and 4b, and 5 are set on the plane, thereby generating the three-dimensional magnetic field on the space on the top of the electromagnets 3a, 3b, 4a, 4b, and 5 on the central axis.
That is, to the position or space to which the three-dimensional magnetic field is applied, the magnetic field generating unit 2 is approached in the arbitrary direction in the space under the control operation of the planar moving mechanism unit 74 and is arranged near the place or space, thereby generating the three-dimensional magnetic field in the space.
The current control unit 96 has, as calibration data, the strength of magnetic field generated in the directions (X, Y, and Z directions) per 1A at the positions (heights) on the central axis O.
Further, the user's operation of the instruction/operation unit 10 controls the current flowing to the electromagnets 3a, 3b, 4a, 4b, and 5 from the power supply devices 6 to 8 to be DC current, vibrating current, and rotating current (due to the vibrating current with the phase difference), thereby generating the static magnetic field, vibrating magnetic field, and rotating magnetic field.
According to the first embodiment, advantageously, the position or space to which the magnetic field is applied is easily approached, thereby arbitrarily applying (generating) the three-dimensional magnetic field with high precision. In particular, in the case of generating the magnetic field with the large amount of change in magnetic field in the axial directions, such as the rotating magnetic field and the vibrating magnetic field in the general medical apparatus with a low position-moving-speed, the amount of movement of the medical apparatus is small without varying the position/posture of the magnetic field generating unit depending on the direction of the generated magnetic field. Thus, the driving speed of the position/posture varying unit is low. Advantageously, the medical apparatus is stably controlled, the size of the position/posture varying unit is reduced, the power consumption is low, the structure is simplified, and the magnetic guiding medical system has the efficient structure.
Further, the electromagnets are arranged on the plane and the magnetic field generating unit is moved only on the plane of the arrangement of the electromagnets. When the living body approaches the space for generating the magnetic field, there is no interference of the magnetic field generating unit or moving mechanism with the living body. Therefore, the moving mechanism is easily controlled and, advantageously, the controllability and stability are improved. Further, the magnetic field generating unit having heavy weight is set under the bed and the center of gravity of the overall apparatus is reduced. Thus, the mechanical stability is improved.
The electromagnets 3a, 3b, 4a, 4b, and 5 are collected in one direction. Near the central axis O, as the electromagnets 3a, 3b, 4a, 4b, and 5 are far from the pole face, the entire generated magnetic fields (Hx, Hy, Hz) in the directions are reduced. Near the central axis O of the electromagnet 5, the direction of the magnetic field does not greatly change (if the strength changes, the magnetic field whose direction does not change is generated.
Referring to
Based on the characteristics, the electromagnets 3a and 3b, the electromagnets 4a and 4b, and the electromagnet 5 have different strengths of magnetic fields at the distance near the pole face. However, when the distance is longer to some degree, the electromagnets 3a and 3b, the electromagnets 4a and 4b, and the electromagnet 5 have the same characteristics of the same strength.
Based on the result shown in
When the deviation of the angle from the instructed target magnetic field to be generated is allowable up to 10 [deg.], the difference in strengths of magnetic field generated in the directions is allowable up to 40%. Therefore, even if being used in a state that the generated magnetic field is roughly controlled with the simple control operation, the magnetic field generating unit 2 can generate the three-dimensional magnetic field under the wide allowable range.
According to the first embodiment, the position of the magnetic field generating unit 2 is moved based on the positional information detected by the position detecting unit 94 as mentioned above, and it is controlled that the magnetic field generating unit 2 always exists substantially directly below the capsule medical apparatus 72 in the body cavity of the patient 23. In other words, referring to
As mentioned above, the capsule medical apparatus 72 having the insertion unit inserted in the body cavity is controlled to generate the optimum magnetic field near the position of the capsule medical apparatus 72.
In this state, the magnetic field generating unit 2 applies the rotating magnetic field to the capsule medical apparatus 72, thereby efficiently propelling forward the capsule medical apparatus 72 and returning it if necessary.
As mentioned above, since the guidable region R is limited to a part of region on the top of the magnetic field generating unit 2, the position of the magnetic field generating unit 2 is controlled based on the positional information of the position detecting unit 94 so that the capsule medical apparatus 72 is within the guidable reign R.
According to the first embodiment, it is controlled that the capsule medical apparatus 72 is within the guidable region R near just on the top of the third electromagnet 5 unit in the magnetic field generating unit 2. In this state, the magnetic field generating unit 2 applies the rotating magnetic field to the capsule medical apparatus 72.
Referring to
The following control operation is considered as an example upon controlling the direction and level of the precisely-generated magnetic field.
As mentioned above, although the difference (deviation in the direction of magnetic field) in the direction of the magnetic field actually-generated from the target direction of the magnetic field is small, the rotating magnetic field is generated, then, the above-mentioned deviation in the direction of the magnetic field is observed as the rotating deviation of the rotation of the capsule medical apparatus 72.
Upon rotating and moving the capsule medical apparatus 72 by applying the rotating magnetic field, the signal processing unit 91 outside the body calculates a rotating-angle speed of the capsule medical apparatus 72 from the continuously obtained images by pattern matching. The rotating-angle speed of the image is compared with the rotating-angle speed of the rotating magnetic field to be generated, and the deviation is calculated between the direction of the magnetic field to be generated and the direction of the magnetic field that is actually generated.
The obtained amount of deviation is fed-back and then the current flowing to the electromagnets 3, 4, and 5 of the magnetic field generating unit 2 is controlled. The rotating-angle speed of the capsule medical apparatus 72 is calculated based on the obtained image. Therefore, the magnetic sensor for detecting the generated magnetic field does not need to be arranged to the capsule medical apparatus 72. Thus, the magnetic field is generated with high precision, and the capsule medical apparatus 72 is smoothly controlled.
That is, the antenna 73j (j=a to i) of the receiving antenna unit 73 receives the signal sent by wireless manner from the capsule medical apparatus 72, and the position of the capsule medical apparatus 72 is detected based on the strength of electromagnetic field (abbreviated to an antenna strength) received by the antenna 73j. The planar moving mechanism 77 moves the magnetic field generating unit 2 based on the positional information so that the capsule medical apparatus 72 is within the guidable reign R.
In the case shown in
Referring to
Referring to
Moving means of the height direction is arranged, thereby setting the magnetic field generating unit 2 at an arbitrary three-dimensional position.
In the state shown in
That is, it is possible to obtain the distance from the capsule medical apparatus 72 to the electromagnets 3 to 5 based on the current position of the capsule medical apparatus 72. Further, it is possible to calculate the values of current flowing to the electromagnet 3 to 5 upon generating the magnetic field in the arbitrary direction based on the data (shown in
The component of the magnetic field in the Z direction is calculated based on the direction and the level of the magnetic field to be generated, and the current flowing to the electromagnet 5 is determined by referring to the data on the generated magnetic field per unit current. Similarly, with respect to the X direction and the Y direction, the current flowing to the electromagnets 3 and 4 is determined.
As will be understood with reference to
Further, the value of the current flowing to the peripheral electromagnets 3a and 3b and electromagnets 4a and 4b may be changed, thereby controlling the generated magnetic field.
As mentioned above, the current of the electromagnet is determined only by the distance D (Z coordinate), and only the magnetic field data on the central axis O may be stored. Therefore, the amount of data stored in the memory unit is reduced. Advantageously, the control algorithm is simplified, the structure is easy, and controllability is stable.
Further, upon generating the magnetic field of a repeating pattern of the rotating magnetic field or vibrating magnetic field, only the maximum value (amplitude) of a current pattern of the electromagnet may be varied depending on the distance D. Therefore, advantageously, the system and the control algorithm are further simplified.
In this case, the capsule medical apparatus 72 is held just on the top of the electromagnet 5 as mentioned above. The distance D between the magnetic field generating unit 2 and the capsule medical apparatus 72 in this case is approximately minimum. Therefore, the magnetic field generated by the magnetic field generating unit 2 on the near distance side is efficiently used, and the capsule medical apparatus 72 can be guided in the region having the matching magnetic field.
Further, when the capsule medical apparatus 72 exists near the magnetic field generating unit 2 and the strength of magnetic field is sufficiently ensured, the upper limit of the strength of the generated magnetic field may be provided. Thus, the power consumption is realized because unnecessary current does not need to flow to the electromagnet.
According to the first embodiment, the receiving antenna unit 73 having a plurality of antennas receives the wireless signals from the capsule medical apparatus 72, and the position of the capsule medical apparatus 72 is calculated based on the antenna strength signal in this case.
The guidable region R is ensured by controlling the current flowing to the electromagnets of the magnetic field generating unit 2 with the positional information, and by moving the magnetic field generating unit 2, the capsule medical apparatus 72 is controlled such that the magnetic field generated by the magnetic field generating unit 2 is set within the guidable region R for magnetic guiding operation. When the rotating magnetic field is applied to the capsule medical apparatus 72 in this state and the capsule medical apparatus 72 is thus moved at the position within the wide range in the body cavity, the relative position between the capsule medical apparatus 72 and the magnetic field generating unit 2 are controlled, thereby holding the capsule medical apparatus 72 at the position for continuously easy guiding operation. Thus, the capsule medical apparatus 72 is magnetically propelled with high smoothness.
Upon applying the rotating magnetic field to the capsule medical apparatus 72 by the joystick 98 for controlling the direction and the joystick 99 for advance and return operation shown in
Then, the image display unit 92 displays the still image.
Upon rotating the capsule medical apparatus 72, the image display unit 92 stops the rotation and displays the image. Then, the user views the image that does not have the image rotation due to the rotation of the capsule medical apparatus 72 displayed on the image display unit 92 and instructs the directional change to the arbitrary directions of vertical and horizontal directions by operating the joystick 98 for controlling the direction.
The propulsion to the forward or backward on the image is instructed by operating the joystick 99 for advance and return operation.
In the case of instructing the propulsion by the joystick 99 for advance and return operation and the spiral structure 89 arranged on the outer-circumferential surface of the capsule medical apparatus 72 is right-spirally arranged, and the joystick 99 for advance and return operation is inclined in the upper direction, the rotating magnetic field is generated in the right rotating direction relative to the front direction on the screen, thereby moving the capsule medical apparatus 72 forward on the screen.
Further, upon inclining downward the joystick 99 for advance and return operation, the rotating magnetic field is generated in the left rotating direction relative to the front direction on the screen, thereby moving backward the capsule medical apparatus 72 on the screen.
According to the first embodiment, upon moving the position of the capsule medical apparatus 72 within the wide range in the body cavity, the relative position between the capsule medical apparatus 72 and the magnetic field generating unit 2 is controlled, thereby continuously holding them at the position for easy magnetic guiding operation and magnetically propelling the capsule medical apparatus 72.
According to the first embodiment, the planar moving mechanism unit 74 has the planar moving mechanism 77 that moves the magnetic field generating unit 2 in the X and Y directions as shown in
Referring to
Referring to
With the above-mentioned structure, the following advantages are obtained.
That is, upon increasing the width of the magnetic field generating unit 2 relative to the width of the bed 31, the magnetic field generating unit 2 is moved only in the longitudinal direction relative to the rectangular bed 31. Therefore, the lateral width of the device is reduced. Further, since the number of driving axes of the magnetic field generating unit 2 having the heavy weight and the large number of wirings is reduced. Thus, the driving part is simple and the overall device is reduced in size and weight, and the efficiency is improved.
That is, the planar moving mechanism 77 arranged on the top surface of the bed supporting base 104 supports the main body of the bed 31 on which the patient 23 is laid. In this case, the magnetic field generating unit 2 is arranged under the bottom side of the bed 31. In this case, since the magnetic field generating unit having the heavy weight and the large number of wirings is fixed, the structure of the driving portion is simple. Thus, the overall device is reduced in size and weight and the efficiency is improved. In particular, upon increasing the sum of the moving range and the width of the magnetic field generating unit relative to the width of bed, the lateral width of the device is reduced.
According to the first embodiment, the planar moving mechanism unit 74 has been used to move the magnetic field generating unit 2 in X and Y directions (to change the area of generated magnetic field above the bed in X and Y directions). In place of this, a tilt moving mechanism can be used (can be replaced with the planar moving mechanism unit 74). The tilt moving mechanism inclines the magnetic field generating unit 2 to change the direction of generated magnetic field. By changing the tilting angle of the magnetic field generating unit 2, the area of magnetic field generated above the bed can be changed to cover the whole guiding area. The tilt moving mechanism can be tilted in two degrees of freedom (i.e. spherically), thus enable to change the area of generated magnetic field above the bed in X and Y directions. The tilt moving mechanism can also be one degree of freedom type (tilts only in a plane) and combined with bed horizontal moving mechanism to achieve X and Y direction movement of the area of generated magnetic field. By only tilting the magnetic field generating unit 2, the space for moving the magnetic field generating unit 2 can be reduced.
According to the embodiment and the like, the position detecting means detects the position by using the signal sent by wireless manner from the capsule medical apparatus 72. However, the positional information may be obtained by using ultrasonic waves as will be described later.
Referring to
The plurality of ultrasonic probes 101a, 101b, . . . adjust the position and angle for the contact state to the body surface of the patient 23 by an adjusting device 102. The adjusting device 102 has a sensor 103 that detects the information on the position and the angle for the contact state to the patient 23 of the plurality of ultrasonic probes 101a, 101b, . . . . The sensor 103 comprises an encoder and a linear encoder to detect the contact position and the angle to the patient 23 of the probes 101a, 101b, . . . .
The sensor 103 outputs the detected information to the planar moving mechanism unit 74 and the magnetic field control unit 95 shown in
The ultrasonic images obtained by the plurality of ultrasonic probes 101a, 101b, . . . are as shown in
The information on the calculated position of the capsule medical apparatus 72 obtained from the plurality of ultrasonic images are outputted to the planar moving mechanism unit 74 and the magnetic field control unit 95 shown in
In place of using the plurality of ultrasonic probes 101a, 101b, . . . , ultrasonic probes 105 and 106 may be used as shown in
Referring to
Referring to
The structure shown in
In this case, the moving range for moving the ultrasonic probe 107 on the bottom of the bed 31 is cut-off, thereby keeping the state in which the top of the ultrasonic probe 107 is in contact with the back of the patient 23.
Further, the position of the capsule medical apparatus 72 is calculated based on the ultrasonic image obtained by the ultrasonic probe 107, and the calculated information on the position is used.
Referring to
The rotating member 110 is rotated, thereby freely opening and closing the ultrasonic probes 111a and 111b that are in contact with the patient 23 and are apart from the patient.
The ultrasonic frequencies of the ultrasonic probes 101a may be varied.
The plurality of ultrasonic probes 101a may be sequentially driven, thereby obtaining the information on the ultrasonic image.
Referring to
Then, an ultrasonic image obtained by the ultrasonic probe array 113 is sequentially outputted to the ultrasonic image display device 115 via an ultrasonic observing device 114 for processing the signals of the ultrasonic probe array 113. Further, the position of the capsule medical apparatus 72 may be calculated from the ultrasonic image and the calculated information on the position may be used.
In the case of detecting the positional information from the image by using the ultrasonic probes 101a, the container 81 of the capsule medical apparatus 72 shown in
Thus, the position of the capsule medical apparatus 72 is easily calculated from the ultrasonic image.
Although the magnetic field generating unit 2 is arranged in the bed 31, as shown in
Next, a description is given of a second embodiment of the present invention with reference to
According to the second embodiment, a magnetic field generating unit 51 for extracorporeally guiding the patient 23 applies the static magnetic field to a magnet 137 arranged to the endoscope 123 inserted in the patient 23, thereby changing the direction of the magnet 137 in the endoscope 123. Therefore, the user, such as an operator, controls the static magnetic field generated by the magnetic field generating unit 51 and changes the direction of the magnet 137 in the desired direction, thereby controlling the direction of the endoscope 123.
The magnetic guiding medical system 121 comprises: the endoscope 123 inserted in the body of the patient 23 placed on a bed 122; a robot arm 124 arranged on one side-surface of the bed 122; the magnetic field generating unit 51 attached to the robot arm 124; and a magnetic sensor 126 arranged on a sensor holding base 125 arranged on the other side surface of the bed 122.
A universal cable 127 of the endoscope 123 is connected to the magnetic guiding medical system 121, and comprises the robot arm 124, the holding base 125, and a control unit 128 connected to the robot arm 124 and the holding base 125 via cables.
According to the first embodiment, the magnetic field generating unit 2 comprises the three sets of electromagnets. However, according to the second embodiment, referring to
A motor 52 rotates the base 11 having the above components around the central axis O of the central electromagnet 5 if necessary, thereby providing a function of a three-dimensional magnetic field generating unit for generating the three-dimensional magnetic field.
Preferably, the motor 52 for driving the rotation is an electromagnetic motor to which the magnetic shield is applied, or a motor (ultrasonic motor, etc.) that is not influenced from the magnetic power.
Irrespective of the rotation, similarly to the first embodiment, the electromagnet is plain-arranged and the magnetic field generating unit is moved only on the plane having the electromagnet. Therefore, when the living body is close to the space for generating the magnetic field, there is no danger of interference between the magnetic field generating unit and the moving mechanism with the living body. Thus, the moving mechanism is easily controlled and, advantageously, the controllability and the stability are improved. Further, the magnetic field generating unit having large weight is arranged under the bed, therefore, the center of the gravity of the entire device is lowered, and the mechanical stability is improved.
Furthermore, the rotation generates the rotating magnetic field.
In addition, since the number of electromagnets is reduced, the device is reduced in size.
The endoscope 123 comprises: an elongated insertion unit 131 that is easily inserted in the body cavity; an operating unit 132 that is arranged at the rear end of the insertion unit 131; and a universal cable 127 extended from the operating unit 132. A connector at the back end of the universal cable 127 is connected to a video processor 133 arranged to the control unit 128.
Referring to
According to the second embodiment, the distal-end portion 134 comprises, on the outer-circumference thereof, a magnet 137 that is magnetized in the axial direction of the distal-end portion 134. By using the magnetic field generated by the magnetic field generating unit 51, the magnetic force operates to the magnet 137, thereby changing the direction of the distal-end portion 134.
Further, a coil 138 for generating an alternating magnetic field is arranged near the outer circumference of the distal-end portion 134. The alternating current is flowed to the coil 138, thereby generating the alternating magnetic field. A magnetic position detecting mechanism detects the position and the direction of the coil 138 by detecting the alternating magnetic field by the magnetic sensor 126 shown in
The magnetic sensor 126 comprises a plurality of magnetic sensor devices, and detects the position of the coil 138 and the axial direction of the coil 38, that is, the direction (posture) of the distal-end portion 134 of the endoscope 123 in the axial direction. The magnetic sensor 126 detects the magnetic field generated by the two-dimensional magnetic field generating unit 51 as well as the alternating magnetic field generated by the coil 138. The two magnetic field signals are separated by filter processing because they have different frequencies.
The signal based on the magnetic field generated by the two-dimensional magnetic field generating unit 51, detected by the magnetic sensor 126, is inputted to the magnetic field control unit in the control unit 128. The magnetic field control unit detects the magnetic field that is actually generated at the position of the distal-end portion 134, and controls the current flowing to the electromagnet of the magnetic field generating unit 51 by the detected information, thereby always generating the optimum magnetic field for magnetically guiding the distal-end portion 134 therenear. Thus, the magnetic field is precisely generated.
The alternating magnetic field signal generated by the coil 138, detected by the magnetic sensor 126, is used to detect the moving speed of the distal-end portion 134 and to detect the acceleration. The information is sent to the control unit 128, thereby realizing the high-level control operation.
Referring to
According to one modification, referring to
The magnet 139 shown in
The robot arm 124 arranged to the side portion of the bed 31 has a vertical moving mechanism 142 at a main body portion 141, and is movable in the vertical direction on the top end side thereof as shown by an arrow.
Further, a top end 141a of the main body portion 141 is rotatable around the axial direction of the main body portion 141. A rotating member forming the planar moving mechanism 144 is rotatably held at the end of the first arm 143 extended in the horizontal direction from the portion.
At the end portion of a second arm 145 extended in the horizontal direction from the rotating member, a rotating member forming a rotating mechanism 146 is rotatably held. The magnetic field generating unit 51 is attached to the rotating member.
An instruction/operation unit 147 is arranged to the top surface of the control unit 128. The operation of the robot arm 124 is controlled and the direction and the level of the static magnetic field generated by the magnetic field generating unit 51 are changed by operating the instruction/operation unit 147. In another expression, the positional relationship (relative position) between the position of the distal-end portion 134 in the endoscope 123 and the position of the magnetic field generating unit 51 is obtained based on the position of the distal-end portion 134 of the endoscope 123, detected by a magnetic position-detecting mechanism and control information sent to the vertical moving mechanism 142 and the planar moving mechanism 144. The magnetic position-detecting mechanism and the control unit 128 form a relative-position detecting mechanism for obtaining the relative position between the distal-end portion 134 of the endoscope 123 and the magnetic field generating unit 51. The control unit 128 controls the position of the magnetic field generating unit 51 via the vertical moving mechanism 142 and the planar moving mechanism 144 based on the information on the relative position obtained by the relative-position detecting mechanism.
Referring to
In the case shown in
In place of moving the component in the vertical direction of the magnetic field generating unit, as shown by a magnetic field generating unit 2G shown in
The structure of the magnetic field generating unit 2G in this case is shown in
The bottom portion 11a is held by the distal end of a screw 62 screwed into a screw hole of a holding unit 61 connected to a bottom portion on the outer circumference. A motor 63 is arranged at the bottom end of the screw 62. The motor 63 is rotated forward or backward based on the positional information, thereby elevating the bottom portion 11a and varying the height position of the central electromagnet 5 to adjust the generated magnetic field.
That is, since the characteristics of the generated magnetic field relative to the distance from the pole face are slightly different between the central electromagnet 5 and the peripheral electromagnets 3a and 3b, the magnetic field in the desired direction and with the desired strength is easily generated relative to the target distance by adjusting the height of the central electromagnet 5 in accordance with the values of the generated magnetic field relative to the distance from the pole face. In this case, the same advantages as those in the case of controlling the current of the electromagnets depending on the distance D according to the first embodiment are obtained.
Incidentally, according to the first embodiment, the same advantages are obtained by changing the height of the electromagnet 5 relative to the electromagnets 3a and 3b and the electromagnets 4a and 4b. Further, according to the second embodiment, similarly to the first embodiment, the current of the electromagnets may be controlled by the distance D.
As mentioned above, according to the second embodiment, the static magnetic force is applied to the magnet 137 or 139 by applying the static magnetic field to the magnet 137 or 139 arranged to the endoscope 123, thereby changing the direction of the endoscope 123 in the desired direction.
Therefore, the user controls the direction of the static magnetic field, thereby changing the distal-end portion 134 of the endoscope 123 in the desired direction. Further, the insertion into the body cavity is easy and the observing direction is changed in the desired direction.
Next, a description is given of a third embodiment of the present invention with reference to
The magnetic guiding medical system 161 comprises: a capsule medical apparatus 162 that is inserted in the body and picks-up images inside the body; and an extracorporeal device 163 that receives image information sent by wireless manner from the capsule medical apparatus 162.
Referring to
The extracorporeal device 163 has a control unit (not shown) in a main body 167 which is substantially quadratic-prism-shaped and stands in the up/down direction. A planar moving mechanism 169 is arranged in front of the quadratic prism, and the planar moving mechanism 169 holds the magnetic field generating unit 51B and a receiving antenna unit 150 in front thereof that are movable in the up/down direction. In this case, the magnetic field generating unit 51B and the receiving antenna unit 150 are moved in the up/down direction, that is, one-axial direction. The planar state of the magnetic field generating unit 51B and the receiving antenna unit 150 is held and, simultaneously, they are slidable in the up/down direction. The receiving antenna unit 150 has the similar function of the receiving antenna unit 73 according to the first embodiment. Similarly to the first embodiment, the receiving antenna unit 150 has a function for detecting the position of the capsule medical apparatus 162. The receiving antenna unit 150 is held by the magnetic field generating unit 51B. Therefore, the detected position of the capsule medical apparatus 162 obtained by using the receiving antenna unit 150 indicates the position and posture relationship (relative position/posture) between the capsule medical apparatus 162 and the magnetic field generating unit 51B. The position/posture of the magnetic field generating unit 51B is controlled by the detected position/posture relationship.
The magnetic field generating unit 51B shown in
The magnetic field generating unit 51B has two sets of electromagnets with high symmetricalness, as compared with the magnetic field generating unit 51 shown in
According to the third embodiment, it is possible to smoothly guide the direction of the capsule medical apparatus 162 for medical action, such as examination using the endoscope, which is inserted into the body cavity, with the magnetic field.
Next, a description is given of magnetic field generating unit according to modifications. The modifications are obtained by modifying or improving the magnetic field generating unit 2 according to the first embodiment. First, a description is given of the case of increasing the generated magnetic field by efficiently using the space.
The electromagnet 5 in the center is formed by winding a coil 13 to a ferromagnetic member unit 12a containing a column-shaped ferromagnetic member having a quadrate cross-section with high permeability. Incidentally, the region R is formed by removing four corners of the ferromagnetic member unit 12a.
In this case, the radius of the region R is a minimum bend radius of the wiring forming the coil 13 and then the wiring has high density.
The electromagnets 3c and 3d and the electromagnets 4c and 4d, which are isosceles-trapezoid-shaped, are arranged around the electromagnet 5 in the center to be close to the outer surface of the coil 13 which is substantially planar. That is, the electromagnets 3c and 3d and the electromagnets 4c and 4d are symmetrically arranged so that the short side corresponds to the inside. The inclined portions of the electromagnets 3c and 3d and the electromagnets 4c and 4d are arranged to be close to the adjacent inclined portions (in the electromagnets 3c and 3d and the electromagnets 4c and 4d) in parallel with each other.
Ferromagnetic member units (magnet core portions) 12b forming the electromagnets 3c and 3d and the electromagnets 4c and 4d comprise isosceles-trapezoid-shaped column members containing ferromagnetic members. The coil 13 is wound to the ferromagnetic member units 12b, thereby forming the electromagnets.
As mentioned above, the electromagnets 3c, 3d, 4c, 4d, and 5 are in close formation on the plane, and the region of close formation hardly has any spaces not shared by the electromagnet. A high magnetic field is efficiently generated.
Next, a description is given of the case of strengthening the generated magnetic field by adding a ferromagnetic member.
Referring to
Incidentally, in addition to the cases with reference to
Incidentally, the ferromagnetic members 41a may be provided independently of the magnet core portion 12 containing the ferromagnetic member. However, the ferromagnetic members 41a which are provided integrally with the magnet core portion 12 easily suppresses the leakage magnetic flux. Thus, the generated magnetic field is further increased.
Next, a description is given of the advantageous structure for uniformizing the magnetic field.
The cross-sectional area of the magnet core portion containing the ferromagnetic member of the electromagnet 5 in the center is wider than those of the ferromagnetic members of the electromagnets 3a and 3b (or 3c and 3d) and the electromagnets 4a and 4b (or 4c and 4d) which are peripherally arranged. This arrangement is used according to the first embodiment.
In addition, on the generation side of the magnetic field of the electromagnet 5 in the center, a ferromagnetic member 41d having the cross-sectional area larger than that of the magnet core portion of the electromagnet is arranged.
In addition, the central portion of the core containing the ferromagnetic member of the electromagnet 5 in the center is caved.
In addition, the ferromagnetic member of the electromagnet 5 in the center is widened toward the side for generating the magnetic field.
With the structure shown in
In the magnetic field generating unit 2E, a ferromagnetic member 41e is arranged onto the pole face on the generating side of the magnetic field of the peripheral electromagnets (although the electromagnets 4a and 4b are shown, the foregoing is applied to the electromagnet 3a and 3b).
As will be understood with reference to
Next, a description is given of a fourth embodiment of the present invention with reference to
The magnetic guiding medical system 151 comprises: the catheter 153 which is inserted in the body of the patient 23 laid on a bed 152; the magnetic field generating units 2F which are arranged to face the side of the bed 152; a planar moving mechanism 154 which is arranged on the bed 152 to move the magnetic field generating units 2F in parallel with each other; a fluoroscopic device 155, such as an X-ray fluoroscopic device for the body of the patient 23; and a control unit (not shown).
The patient 23 is viewed through the fluoroscopic device 155, and the position of the distal end of the catheter 153 is detected. The position information is used for controlling the direction of the distal end of the catheter 153 in the desired direction. That is, the fluoroscopic device 155 functions as a fluoroscopic-type position detecting mechanism which detects the position/posture of the distal end of the catheter 153. Further, a position/posture relationship (relative position/posture) between the distal end of the catheter 153 and the magnetic field generating units 2F is obtained based on an output from the fluoroscopic-type position detecting mechanism and the control information for controlling the planar moving mechanism 154 which changes the position of the magnetic field generating units 2F, from the control unit (128 according to the second embodiment). That is, the fluoroscopic device 155 and the control unit form the relative position/posture detecting mechanism. Based on the relative position/posture information, the position/posture of the magnetic field generating unit 2F is controlled by the control unit.
Referring to
Incidentally, referring to
A solid line shows the density of magnetic flux to the positions of the first, second, and third electromagnet units. On the other hand, a dotted line shows the facing arrangement of the third electromagnet unit 5 to one part. As will be understood from the characteristics shown by the dotted line, at the far position from the magnetic field generating unit, the magnetic field is increased and the smooth magnetic field is generated (with the small change in strength of magnetic field and in angle of magnetic field, relative to the space).
Referring to
Incidentally,
Further,
The magnetic sensor 159 controls the magnetic field with higher precision. Since the direction of the distal end of the catheter is limited to some degree by the lumen in the body, the direction of the generated magnetic field does not necessarily match the direction of the catheter 153. Then, the magnetic field which is actually generated at the distal end of the catheter is calculated with high precision based on an output value from the magnetic sensor 159 and the position/posture obtained by the fluoroscopic device 155. Thereby, the magnetic field is generated with high precision and stability by the feedback operation of the difference between the direction of the magnetic field to be actually generated and the magnetic field that is actually generated.
Incidentally, the magnetic sensor 159 detects the strength and the direction of the generated magnetic field, that is, the static magnetic field, generated by the magnetic field generating units 2F for guiding operation. The detected signal, by connecting a signal line (not shown) extended from the rear end of the catheter 153 to the control unit, is inputted to a position detecting unit of the control unit. The calculated position and direction are displayed on a display unit (not shown), thereby enabling the replacement of the fluoroscopic device 155.
The user refers to information displayed on the display unit and operates the instruction/operation unit, thereby controlling the direction of the distal end part of the catheter 153.
Incidentally, referring to
Next, a description is given of the fifth embodiment of the present invention with reference to FIGS. 55 to 64B. The fifth embodiment corresponds to modifications of the first and second embodiments. The features according to the fifth embodiment will be described.
Although the position/posture varying unit mainly moves the magnetic field generating unit 2, thereby changing the position/posture according to the first embodiment, the magnetic field generating unit 2 is fixed and a position/posture varying unit 74D of the bed 31 varies the position/posture in the magnetic guiding medical system 180 according to the fifth embodiment, thereby magnetically guiding the system. The position/posture varying unit 74D is controlled by a position/posture control unit 192 forming a control unit 191. The magnetic field generating unit 2 is controlled by a magnetic field control unit 95.
Specifically, referring to
Referring to
Further, according to the fifth embodiment, referring to
The drive coil 181 is driven by a drive-signal generating unit 183, and the signal detected by the sensing coil 182 is inputted to a position/posture detecting unit 184.
The signal detected by the position/posture detecting unit 184 is outputted to the position/posture control unit 192 of the control unit 191 and the magnetic field control unit 95, thereby being used for control operation thereof.
The calibration data is used so as to precisely detect the position/posture of the marker coil 172a. Therefore, according to the fifth embodiment, a calibration data storing unit 185 for storing the calibration data is arranged, and the calibration data is used for the detection of the position/posture using the position/posture detecting unit 184.
As mentioned above, the container 81 comprises the marker coil 172a for detecting the position of the capsule medical apparatus 72B. The marker coil 172a and a condenser 172b form a resonant circuit 172 which is resonant at a predetermined frequency. Incidentally, the container 81 accommodates therein the image pickup device 84 shown in
Under the bed 31, the magnetic field generating unit 2 is arranged. The magnetic field generating unit 2 comprises five electromagnets arranged on the plane, and has the structure shown in
Further, under the bed 31, the drive coil 181 for generating the alternating magnetic field is fixed onto the top surface of the magnetic field generating unit 2.
The above-mentioned arrangement of the drive coil 181 always keeps a relative positional relationship between the marker coil 172a and the drive coil 181 to be under a stable and high detecting-precision condition, under which the marker coil 172a exists within a strong magnetic field generated by the drive coil 181. This is because the control operation is performed to prevent the large change in relative position between the electromagnets in the magnetic field generating unit 2 and the capsule medical apparatus 72B.
Referring to
The ferromagnetic member of the magnetic field generating unit 2 influences on the coil characteristics of the drive coil 181 and the sensing coil 182. However, the above-mentioned structure prevents the change in positional relationship between the magnetic field generating unit 2 and the sensing coil 182 and drive coil 181 if the position of the magnetic field generating unit 2 changes. Therefore, the characteristics of the sensing coil 182 and the drive coil 181 do not change, and the detecting precision is improved.
Under the control operation, under which the relative positional relationship between the electromagnet of the magnetic field generating unit 2 and the capsule medical apparatus 72B does not change, the relative positional relationship between the marker coil 172a and the drive coil 181 and sensing coil 182 does not change. Therefore, with the sensing coil 182, serving as the reference, the control operation does not have any problems in the narrow detected region for detecting the position or posture of the capsule medical apparatus 72B by the position/posture detecting unit 184. Thus, the number of sensing coils 182 is reduced, the amount of calculation for obtaining the position/posture is reduced, and the algorithm for obtaining the position/posture is simple.
In particular, when the drive coil 181 is fixed to the magnetic field generating unit 2, the magnetic field generating unit 2, which influences on the magnetic field for detecting the position, is integrated to both the coils (drive coil 181 and sensing coil 182) for detecting the position. Therefore, the change in calibration data due to the change of the planar moving mechanism (position/posture varying unit) is small. The position is stably detected (because the change in output of the drive coil is small relative to the output of the marker coil).
Further, the calibration data is influenced from the change in relative position among the drive coil 181, the sensing coil 182, and the ferromagnetic member in the chamber. According to the fifth embodiment, when the drive coil 181 and the sensing coil 182 are fixed to the base together with the magnetic field generating unit 2, the change of the planar moving mechanism (position/posture varying unit) does not change the relative position among the drive coil 181 and sensing coil 182 and the magnetic field generating unit 2, and the ferromagnetic member in the chamber. Thus, the change of the planar moving mechanism (position/posture varying unit) does not change the influence of the ferromagnetic member in the chamber, and the amount of change in the calibration data due to the change of the planar moving mechanism (position/posture varying unit) is small. As a consequence, the position is stably detected.
Referring to
The plurality of sensing coils 182 receive both the alternating magnetic field generated by the drive coil 181 and the alternating magnetic field generated by the marker coil 172a, and output the detected data. Here, the information on the alternating magnetic field generated by the drive coil 181 is processed by processing using calibration data, which will be described later, thereby being canceled. As a result, only the information of the alternating magnetic field generated by the marker coil 172a is obtained by the detected data of the plurality of sensing coils 182.
Referring to
The position/posture detecting mechanism 171 comprises: the marker coil 172a arranged in the capsule medical apparatus 72B inserted in the patient 23, serving as the living body; the drive coil 181 and the plurality of sensing coils 182 (or may be magnetic sensors) arranged outside the patient 23; the drive-signal generating unit 183 for generating the alternating magnetic field to the drive coil 181; the position/posture detecting unit 184 for calculating the position or the posture of the capsule medical apparatus 72B based on output signals from the sensing coils 182; and the calibration data storing unit 185 for storing the calibration data.
Here, the calibration means that, before guiding (inserting) the capsule medical apparatus 72B including the marker coil 172a into the patient 23, that is, in the state in which the marker coil 172a is not arranged in the detected area, only the drive coil 181 is driven, the alternating magnetic field is generated, and the strength of magnetic field is then measured. The calibration data indicates the data on the strength of magnetic field measured in this case.
The drive coil 181 generates the alternating magnetic field by supplying a drive signal from the drive-signal generating unit 183. Guiding current flows to the marker coil 172a by using the alternating magnetic field, and the alternating magnetic field is additionally generated. The plurality of sensing coils 182 are arranged and detect the strength of magnetic field generated by the drive coil 181 and the sensing coils 182 at the arrangement positions thereof.
The position/posture detecting unit 184 detects the position or the posture of the marker coil 172a by dipole approximation, or the like, of the magnetic field of the marker coil 172a based on the difference between the outputs of the sensing coils 182 and the data (calibration data) of the strength of magnetic field generated only by the drive coil 181 measured before guiding the capsule medical apparatus 72B into the patient 23.
The following advantages are obtained by using the structure shown in
That is, the position detection using the magnetic field suppresses the influence from the attenuation due to the living body, thereby detecting the position with high precision. Due to detecting the position by using the alternating magnetic field, the generation of the alternating magnetic field of another frequency by the magnetic field generating unit 2 does not influence on the positional detection with the arrangement of a filter for limiting a frequency band to the sensing coils 182.
Incidentally, the magnetic field generated by the drive coil 181 may be a pulse magnetic field. The generated pulse magnetic field guides the current to the marker coil 172a, and the alternating magnetic field is generated while the resonant circuit 172 attenuates the current. The sensing coil 182 detects the magnetic field in this case. In this case, since only the magnetic field of the marker coil 172a is detected by the sensing coil 182, the calibration is not necessary and the system structure is simplified.
Referring to
Further, since the magnetic field generating unit 2 and the drive coil 181 are not moved together therewith, the increase in size of the drive coil 181 does not influence on the size (width and length) of the bed 31 and the size of device is therefore reduced.
Referring to
By arranging the sensing coils 182 to the bed 31, the magnetic field generating unit 2 and the sensing coils 182 are separated. If the sensing coils 182 are widely arranged so as to increase the detecting range, this does not influence on the size and the movable range (width and length) of the bed 31 and the size of device is therefore reduced.
The sensing coil 182 has the coil detecting characteristics that change near the magnetic field generating unit 2, serving as a ferromagnetic member. Referring to
Referring to
When the drive coil 181 is arranged onto the bed 31 in the vertical direction, the change in planar moving mechanism does not move the sensing coils 182. The three-dimensional magnetic field is easily generated and the position/posture is stably detected.
Next, a description is given of the operation of a magnetic guiding method of the magnetic guiding medical system 180 shown in
Referring to
In the calibration, the position/posture varying unit 74D changes the position of the bed 31 and, simultaneously, the sensing coils 182 detect the output of drive coil 181 at each position (typical position) thereof.
The outputs of the sensing coils 182 are stored in the calibration data storing unit 185 associated with the position of the bed 31.
After the calibration of the position/posture detecting unit 184, referring to
As mentioned above, based on the position/posture detected information of the position/posture detecting unit 184, the control unit 191 and the magnetic field control unit 95 control the bed 31 and the generated magnetic field, thereby stably performing the magnetic guiding operation of the capsule medical apparatus 72B. Specifically, based on calibration data near the current position of the bed 31, a calibration value is obtained by approximation and estimation at the current position.
Based on the difference between the outputs of the sensing coils 182 and the obtained calibration value, the position/posture detecting unit 184 calculates the position/posture of the capsule medical apparatus 72B.
The bed 31 is moved so that the central axis of the magnetic field generating unit 2 is at the calculated position.
Similarly to the first embodiment, the balance of current flowing to the electromagnets is controlled, based on the information on the obtained position of the capsule medical apparatus 72B and the distance information of the height direction of the magnetic field generating unit 2, so that the magnetic field control unit 95 generates a desired magnetic field at the position of the capsule medical apparatus 72B.
According to the fifth embodiment, with the above-mentioned control operation, the following advantages are obtained.
That is, since the drive coil 181 and the sensing coils 182 are fixed to the magnetic field generating unit 2, the position is not precisely detected without arranging the capsule medical apparatus 72B onto the magnetic field generating unit 2. Then, the bed 31 is moved and the position suitable to the detection is scanned, thereby detecting the position for precise positional detection and setting the magnetic field generating unit 2. From the start timing of the guiding operation, the stable control is possible.
Before generating the magnetic field from the magnetic field generating unit 2, the position/posture of the magnetic field generating unit 2 and the capsule medical apparatus 72B is caused to be within a predetermined range of the relative position/posture, thereby generating the magnetic field suitable to the guiding operation from the start timing of the guiding operation and realizing the stable control operation.
Next, a description is given of a feedback method of the position/posture information from the capsule medical apparatus 72B to the magnetic field control unit 95 according to another modification with reference to
Similarly to the above-mentioned control method, the position of the bed 31 is moved so that the central axis of the magnetic field generating unit 2 matches the capsule medical apparatus 72B. Then, the position/posture is detected again. Here, the obtained posture (direction) of the capsule medical apparatus 72B matches the direction of the magnetic field which is actually generated.
The magnetic field control unit 95 controls and compensates for the current flowing to the electromagnets based on the difference between the direction of the magnetic field to be actually generated and the direction to be originally generated, in order to generate a desired magnetic field.
Further, a description is given of the sequence until starting the guiding operation according to another modification.
Upon guiding the capsule medical apparatus 72B into the patient 23 on the bed 31, the initial position/initial posture of the patient 23 is determined in advance, and the capsule medical apparatus 72B is guided into the patient 23 at the predetermined position/posture. In this case, the bed 31 is marked and the initial position or the initial posture of the patient 23 is determined with the mark. As a mark, a line, serving as the reference may be provided for the bed 31, or laser may be used. Further, the movement of the bed 31 may determine the initial position and the initial posture of the patient 23.
In this case, the bed 31 is moved so that the central axis of the magnetic field generating unit 2 is positioned near the guiding position of the capsule medical apparatus 72B. Further, the position may be detected after moving the magnetic field generating unit 2 and the fine control operation may be performed so that the central axis of the magnetic field generating unit 2 matches the capsule medical apparatus 72B.
Then, the detection of the best position does not need the movement of the bed 31 and, advantageously, the movement to the initial position is possible in a short time. Further, advantageously, the fine control operation sets the position of the bed 31 to the best initial position.
Incidentally, in place of guiding the capsule medical apparatus 72B in the patient 23 on the bed 31, the capsule medical apparatus 72B may be arranged at a predetermined position on the bed 31. In this case, the arrangement position of the capsule medical apparatus 72B may match the central axis of the magnetic field generating unit 2. Further, after the predetermined arrangement position of the capsule medical apparatus 72B matches the central axis of the magnetic field generating unit 2, the positional detection starts and the bed 31 is moved so that the position of the capsule medical apparatus 72B matches the central axis of the magnetic field generating unit 2. In this state, the capsule medical apparatus 72B is guided in the body of the patient 23, thereby starting the guiding operation. Then, the following advantages are obtained.
That is, since the initial position of the capsule medical apparatus 72B is determined with respect to the bed 31, the position of the bed 31 is easily set to the best initial position.
When the drive coil 181 and the sensing coils 182 are fixed to the bed 31 to detect the position, the position is detected when the capsule medical apparatus 72B is guided. The bed may be moved so that central axis of the magnetic field generating unit 2 matches the detected position.
Then, since the position detecting range is wide, the bed 31 is not moved so as to search the position of the capsule medical apparatus 72B. Advantageously, the bed is moved to the initial position in a short time.
Incidentally, according to the fifth embodiment, the magnetic field generating unit 2 is fixed and the bed 31 is moved. The present invention can be applied to the case of moving the magnetic field generating unit 2 according to the first embodiment.
The above-mentioned methods have the similar advantages in the case of another positional detection using electrical waves or the ultrasonic waves.
Referring to
The above-mentioned structure gives the following advantages.
That is, the electromagnet core member and the auxiliary magnetic-pole portion comprise a conductive ferromagnetic member containing iron or Nickel. In this case, the eddy current is generated in alternating magnetic field used by the position detection (position/posture detecting unit 184), thereby influencing on the spatial distribution of alternating magnetic fields. Thus, the positional detecting precision deteriorates. Then, the insulator 196 finely partitions the core portion and the ferromagnetic member 195, serving as an auxiliary magnetic-pole portion, thereby suppressing the eddy current without changing the strength of the generated magnetic field and improving the stability and precision of the position/posture detection. As a consequence, the improvement of the stability and precision of the position/posture for feedback operation raises the precision of the generated magnetic field generated near the insertion unit and enables the stable control operation.
Incidentally, another embodiment structured by partly combining the above-mentioned embodiments belongs to the present invention.
A living-body inserting medical apparatus, such as a capsule medical apparatus inserted in the body, includes a magnet or the like operated by the magnetic field. The position of the living-body inserting medical apparatus is detected upon magnetically guiding the living-body inserting medical apparatus by a magnetic field generating unit which is arranged to the outside of the body to detect and control the positional movement of the magnetic field generating unit. Thus, even when the living-body inserting medical apparatus is widely moved in the body, the magnetic field for guiding operation is generated using the magnetic field generating unit.
Number | Date | Country | Kind |
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2004-227214 | Aug 2004 | JP | national |
2005-192628 | Jun 2005 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/JP05/14608 | 8/3/2005 | WO | 1/18/2007 |