JP2003265436A - Magnetic resonance imaging apparatus and safety system for magnetic resonance imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent tools used for operation and peripheral devices whose approach to the leakage magnetic field generated by a magnetic resonance imaging apparatus is not preferable from approaching the leakage magnetic field and to avoid dangerous state caused by approach even in the case of approach. <P>SOLUTION: In an operating room, operating tools, tool stands carrying the tools, and peripheral devices such as a drip, an electrocardiograph and a microscope for operation are existent in addition to the magnetic imaging apparatus for testing and a bed. These devices are formed of magnetic substance, so they have high risk of being magnetized by leakage magnetic field from the magnetic resonance imaging apparatus and attracted. Magnetic sensor means are disposed in all spaces of the magnetic resonance imaging apparatus, peripheral devices or operating room, the magnetic field strength in the operating room is detected by the magnetic sensor means, and if it enters the dangerous state, a warning is given by the display means, or the moving magnetic resonance imaging apparatus is stopped or moved backward. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention improves the safety when operating a magnetic resonance imaging apparatus for taking a tomographic image of a desired part of a human body as a subject by utilizing a nuclear magnetic resonance phenomenon in an operating room. The present invention relates to a magnetic resonance imaging apparatus and a safety system for a magnetic resonance imaging apparatus.

[0002]

2. Description of the Related Art A magnetic resonance imaging apparatus uses a magnetic field generating means to apply a static magnetic field and a gradient magnetic field to a subject, and further irradiates the subject with a high frequency magnetic field pulse to cause nuclear magnetic resonance in the subject. At that time, an echo signal emitted from the subject is detected, and the detected echo signal is processed to capture the density distribution, relaxation time distribution, etc. of nuclear spins in the subject as a tomographic image. The static magnetic field for generating such a nuclear magnetic resonance phenomenon must have a spatially and temporally uniform intensity and direction. The static magnetic field generating means for generating such a static magnetic field is roughly classified into one using a permanent magnet, one using a superconducting magnet and a normal conducting magnet.

These static magnetic field generating means always generate a leak magnetic field outside when generating a static magnetic field. Since a magnetic resonance imaging apparatus is usually used in a hospital, it is important to take safety measures for a person using a pacemaker. Further, the leakage magnetic field generated from the static magnetic field generating means not only affects the pacemaker, but also when the ferromagnetic material such as iron approaches the static magnetic field generating means, the leakage magnetic field magnetizes the ferromagnetic material, A large force is attracted in the direction of the static magnetic field generating means. This attracting force increases as the size of the ferromagnetic material increases and the magnetic permeability increases. Therefore, normally, the ferromagnetic material is not brought into the examination room in which the magnetic resonance imaging apparatus is installed.

[0004]

At present, non-transcutaneous treatment (IVR: Inter Ve
National Radiography) has become commonplace, and a magnetic resonance imaging apparatus has come to be used as an image diagnostic apparatus. Therefore, the magnetic resonance imaging apparatus has come to be installed in the operating room, and during the operation, it is necessary to keep the subject away from the magnetic field region and, if necessary, carry the subject to the imaging region of the magnetic resonance imaging device. I was going.

FIG. 1 is a diagram showing a conventional schematic configuration in which a magnetic resonance imaging apparatus is installed in an operating room and a non-percutaneous treatment is performed there. In the figure, a leakage magnetic field 100a is generated around the magnetic resonance imaging apparatus 100. In the figure, about 5 Gauss lines are shown abstractly. A patient 101, which is a subject, lies on a bed 102. The head of the patient 101 is a surgical operation fixture 10
It is fixed at 3. The vicinity of the surgical unit fixing tool 103 is called a surgical field 104. This surgical field 104 is the leakage magnetic field 100a.
It does not fit within the 5 Gauss line. Peripheral devices 105 to 107 such as a drip, an electrocardiograph, and a surgical microscope are provided around the patient 101 (bed 102). In addition, the surgical instrument 10 is provided near the surgical unit fixing tool 103.
A surgical instrument table 109 equipped with 8 is provided. The operator 110 performs an operation using these peripheral devices 105 to 107 and the surgical instrument 108.

However, among the surgical instruments 108, the forceps or the like and peripheral devices 105 to 107 used during surgery are usually made of a magnetic material, and are therefore affected by the leakage magnetic field 100a from the magnetic resonance imaging apparatus 100. Inadvertently accidentally place these surgical instruments 10 in a stray magnetic field.
8 and the peripheral devices 105 to 107 are brought close to each other, they are attracted toward the magnetic resonance imaging apparatus 100,
There was a problem of being in a dangerous state. In addition, there is a problem that the peripheral devices 105 to 107 malfunction due to the influence of the leakage magnetic field 100a. Further, since the hemostatic clip used in the surgery is also made of a magnetic material, when the patient 101, which is the subject, is affected by the leakage magnetic field 100a, the hemostatic clip is detached and sucked by the magnetic resonance imaging apparatus 100. There is also a problem that the patient 101 is put in a dangerous state.

The present invention has been made in view of the above points, and it is not preferable to approach the leak magnetic field generated by the magnetic resonance imaging apparatus such as instruments and peripheral equipment used for surgery. An object of the present invention is to provide a magnetic resonance imaging apparatus and a safety system for the magnetic resonance imaging apparatus, which can prevent the magnetic resonance imaging apparatus from approaching the leakage magnetic field.

Further, according to the present invention, even when a device which is not preferable to approach the leakage magnetic field generated by the magnetic resonance imaging apparatus, such as an instrument or peripheral equipment used for surgery, approaches the leakage magnetic field. Another object of the present invention is to provide a magnetic resonance imaging apparatus and a safety system for a magnetic resonance imaging apparatus capable of avoiding a dangerous state caused by the above.

[0009]

According to a first aspect of the present invention, there is provided a magnetic resonance imaging apparatus comprising: a bed on which a subject is mounted; and a magnetic resonance imaging for moving a radiographing chamber to capture a tomographic image of the subject on the bed. In the apparatus, magnetic sensor means for detecting a magnetic field that changes depending on an object that is arranged near or in the vicinity of the magnetic resonance imaging apparatus and that relatively approaches, and the magnetic sensor means detects a change in the magnetic field of a predetermined value or more. In this case, a display means for displaying a warning indicating this is provided. In the radiographing room, in addition to a magnetic resonance imaging apparatus for examination and a bed, surgical instruments, an instrument table on which the instruments are mounted, peripheral devices such as a drip, an electrocardiograph, and a surgical microscope exist. Normally, surgical instruments and peripheral devices are made of magnetic material, so they are magnetized by the leakage magnetic field from the magnetic resonance imaging device,
High risk of being inhaled. In view of this, in the present invention, magnetic sensor means is provided on the magnetic resonance imaging apparatus, and the magnetic field that changes depending on an object relatively approaching the magnetic resonance imaging apparatus is detected using the magnetic sensor means. When a change in the magnetic field greater than or equal to the value is detected, the display unit is used to warn the operator or the like in the imaging room. As a result, an operator or the like in the imaging room can perform work while being careful not to approach objects such as instruments that are not desirable to approach in the leakage magnetic field into the leakage magnetic field.

A magnetic resonance imaging apparatus according to a second aspect of the present invention is a magnetic resonance imaging apparatus in which a bed on which a subject is mounted and a tomographic image of the subject on the bed that moves in an imaging chamber are captured. A magnetic sensor means for detecting a magnetic field arranged near or in the vicinity of the peripheral equipment means provided with movable peripheral equipment means, and when a magnetic field having a certain strength or more is detected by the magnetic sensor means. A display means for displaying a warning indicating that is provided. Peripheral devices such as surgical instruments and instrument stands equipped with them, drip, electrocardiographs, and surgical microscopes are movable, so there is a risk of being sucked when the magnetic resonance imaging apparatus approaches. Therefore, these peripheral devices are provided with magnetic sensor means to display a warning when the peripheral devices enter a magnetic field having a certain strength or more.
This makes it possible to prevent peripheral devices that are at risk of being attracted from approaching the stray magnetic field of the magnetic resonance imaging apparatus.

A magnetic resonance imaging apparatus according to a third aspect is the magnetic resonance imaging apparatus according to the first or second aspect, further comprising movement control means for controlling the movement of the magnetic resonance imaging apparatus according to the detection result of the magnetic sensor means. . This is because the detection result of the magnetic sensor means, that is, when the magnetic sensor means provided in the magnetic resonance imaging apparatus detects a change in the magnetic field of a predetermined value or more, the magnetic sensor means provided in the peripheral device means makes it constant. When a magnetic field higher than the strength is detected, a warning is displayed by the display means and the movement of the magnetic resonance imaging apparatus is stopped or retracted to avoid a dangerous state due to the leakage magnetic field of the magnetic resonance imaging apparatus. I chose

A magnetic resonance imaging apparatus according to a fourth aspect is a magnetic resonance imaging apparatus for moving a tonographic image of the subject on the bed and a bed on which the subject is mounted, and wherein the tomographic image of the subject on the bed is taken. A plurality of magnetic sensor means, and a display means for displaying so as to identify the magnetic sensor means that has detected a magnetic field of a certain strength or more among the plurality of magnetic sensor means. This is because by arranging a plurality of magnetic sensor means in the radiographing room and specifying a magnetic field having a certain strength or higher, the range in which the influence of the leakage magnetic field of the magnetic resonance imaging apparatus spreads and the movement In the case of the magnetic resonance imaging apparatus of the type, it is possible to easily recognize how the range of the leakage magnetic field changes due to the movement. When the magnetic resonance imaging apparatus is fixed, it may be provided in the vicinity of the magnetic resonance imaging apparatus affected by the leakage magnetic field, and in the case of a movable type, it may be provided in the vicinity of its moving range. In the case of claim 1, 2 or 3, a display means may be provided.

According to a fifth aspect of the present invention, in the magnetic resonance imaging apparatus according to the fourth aspect, at least one of the magnetic sensor means is arranged on a ceiling or a floor surface of an imaging room. This relates to where in the photographing room the magnetic sensor means is installed, and is suspended from the ceiling, provided on the floor surface, or embedded in the floor surface. By thus being provided on the ceiling or floor, it is possible to easily recognize to what extent the magnetic substance may be brought in.

A magnetic resonance imaging apparatus according to a sixth aspect of the present invention is the magnetic resonance imaging apparatus according to the fourth or fifth aspect, wherein at least one of the magnetic sensor means is installed in the vicinity of the surgical field such as the bed or the surgical site fixture. This also relates to where in the imaging room the magnetic sensor means is installed, and is provided near the surgical field where surgery is actually performed. With this, it is possible to easily confirm whether it is safe to bring a surgical instrument into the surgical field.

A magnetic resonance imaging apparatus according to a seventh aspect is the magnetic resonance imaging apparatus according to the fourth, fifth or sixth aspect, wherein at least one of the magnetic sensor means is worn by an operator or an operator in an imaging room. This also relates to where in the imaging room the magnetic sensor means is installed, and is provided to an operator or an operator who may move in the imaging room. Since it is worn by the operator or operator who may move in the imaging room, it is safe for the operator or operator holding the surgical tool or magnetic material to enter the leakage magnetic field of the magnetic resonance imaging system. Moreover, it is possible to easily confirm whether or not the magnetic field is not affected by the leakage magnetic field.

A magnetic resonance imaging apparatus according to an eighth aspect is the magnetic resonance imaging apparatus according to any one of the first to seventh aspects, wherein the display means is a monitor means that can be mounted on a head of an operator or an operator. Is. This is related to a display means for displaying a warning, and what is called a head mounted display that can be mounted on the head of an operator or an operator who is in the photographing room is used as the display means by using the monitor means. Is. Since the monitor is mounted on the head and the monitor is always located in the wearer's field of view, it is possible to instantly recognize that there is a danger due to the leakage magnetic field when the warning is displayed.

According to a ninth aspect of the present invention, there is provided the magnetic resonance imaging apparatus according to any one of the first to seventh aspects, wherein the display means is composed of monitor means installed in a photographing room. This is also related to the display means for displaying the warning, and the monitor means provided in the photographing room is used as the display means. Since such monitor means is provided in the photographing room, it is possible for all persons in the photographing room to easily recognize that there is a danger due to the leakage magnetic field.

A magnetic resonance imaging apparatus according to a tenth aspect of the present invention is the magnetic resonance imaging apparatus according to any one of the first to seventh aspects, wherein the display means is composed of a sounding means installed in a photographing room. This also relates to a display means for displaying a warning, and a sounding means such as a speaker provided in the photographing room is used as the display means. In the case of monitor means, you cannot know what kind of situation you are in unless you look at the monitor positively, but if you pronounce a voice etc., you should call the attention evenly to all the people in the shooting room. You can

A magnetic resonance imaging apparatus according to claim 11 is the magnetic resonance imaging apparatus according to any one of claims 1 to 7, wherein the display means comprises a warning indicator light provided adjacent to the magnetic sensor means. Is. This also relates to display means for displaying a warning, and when a plurality of magnetic sensor means are provided in the photographing room, a warning indicator lamp is provided for each magnetic sensor means. Since the warning indicator light is provided in each magnetic sensor means, by turning on or blinking the warning indicator light adjacent to the magnetic sensor means in which a magnetic field having a certain strength or more is detected, the warning indicator light is turned on or blinks. It can be easily recognized that the vicinity of the magnetic sensor means is in a dangerous state due to the leakage magnetic field of the magnetic resonance imaging apparatus, and the vicinity of the magnetic sensor means which is not so is relatively safe.

A magnetic resonance imaging apparatus according to a twelfth aspect of the present invention is the magnetic resonance imaging apparatus according to any one of the fourth to eleventh aspects, wherein the magnetic resonance imaging apparatus is configured to be movable and the magnetic resonance imaging apparatus detects the magnetic field in accordance with a detection result of the magnetic sensor means. It is provided with a movement control means for controlling the movement of the resonance imaging apparatus. This is because the magnetic resonance imaging apparatus is configured to be freely movable in the radiographing room, and the detection result of the magnetic sensor means, that is, the magnetic sensor means provided in the magnetic resonance imaging apparatus changes the magnetic field above a predetermined value. When detected, when a magnetic field of a certain strength or higher is detected by the magnetic sensor means provided on the peripheral device means, a warning indicating that fact is displayed and the movement of the magnetic resonance imaging apparatus is stopped or retracted. By doing so, a dangerous state due to the leakage magnetic field of the magnetic resonance imaging apparatus is avoided.

According to a thirteenth aspect of the present invention, there is provided a magnetic resonance imaging apparatus in which a bed on which a subject is mounted and a magnetic resonance imaging apparatus which moves in a radiographing room to capture a tomographic image of the subject on the bed are used. When an object existing within a certain value is detected by the object detecting means, the object detecting means is arranged near or in the vicinity of the imaging device and detects the distance to the object which is relatively close to the object. And a display unit for displaying the warning shown. This is to detect an object approaching a magnetic resonance imaging apparatus moving within a radiographing room within a certain value and display a warning. When the object is a magnetic material, it is magnetized and attracted by approaching the magnetic resonance imaging apparatus, so that such an object is prevented from approaching the magnetic resonance imaging apparatus within a certain value. Further, since the magnetic resonance imaging apparatus is moving in the imaging room, it is possible to perform smooth movement by detecting an object existing on the movement path and removing it in advance.

According to a fourteenth aspect of the present invention, there is provided a magnetic resonance imaging apparatus, a bed on which a subject is mounted, a magnetic resonance imaging apparatus which moves in a radiographing room to capture a tomographic image of the subject on the bed, and the magnetic resonance. A magnetic sensor means for detecting a magnetic field that changes due to an object that is disposed near or in the vicinity of the imaging device and is relatively close to the imaging device; and when the magnetic sensor means detects a change in the magnetic field of a predetermined value or more, And a movement control means for controlling the movement of the resonance imaging apparatus. this is,
A magnetic sensor means is provided on the magnetic resonance imaging apparatus,
The magnetic sensor means is used to detect a magnetic field that changes with an object that is relatively close to the magnetic resonance imaging apparatus, and when a change in the magnetic field of a predetermined value or more is detected, The movement is stopped or retracted to avoid a dangerous state due to a leakage magnetic field of the magnetic resonance imaging apparatus.

According to a fifteenth aspect of the present invention, there is provided a magnetic resonance imaging apparatus comprising: a bed on which a subject is mounted; a magnetic resonance imaging apparatus which moves in a radiographing room to capture a tomographic image of the subject on the bed; A magnetic sensor means for detecting a magnetic field arranged near or in the vicinity of the peripheral equipment means provided with a movable peripheral equipment means, and when a magnetic field having a certain strength or more is detected by the magnetic sensor means. A movement control means for controlling the movement of the magnetic resonance imaging apparatus. This is because the magnetic sensor means is provided in the peripheral device, and when the peripheral device comes into a magnetic field having a certain strength or more, the magnetic resonance imaging apparatus is stopped or moved backward to move the magnetic field. This is to avoid a dangerous state due to the leakage magnetic field of the resonance imaging apparatus.

According to a sixteenth aspect of the present invention, there is provided a magnetic resonance imaging apparatus, a bed on which a subject is mounted, a magnetic resonance imaging apparatus which moves in a radiographing room to capture a tomographic image of the subject on the bed, and the magnetic resonance. In the case where an object existing within a certain value is detected by the object detecting means, which detects the distance between the object and the object which are relatively close to each other and are arranged in the vicinity of the imaging device or close to each other,
And a movement control means for controlling the movement of the magnetic resonance imaging apparatus. This is because when an object approaching the magnetic resonance imaging apparatus moving within the imaging room is detected within a certain value, the movement of the magnetic resonance imaging apparatus is stopped or retracted, and the magnetic resonance imaging apparatus leaks. It is designed to avoid a dangerous state due to a magnetic field.

According to a seventeenth aspect of the present invention, there is provided a magnetic resonance imaging apparatus which warns when a predetermined condition is satisfied on the basis of sensor means for detecting information that changes depending on a relatively approaching object and information detected by the sensor means. And a magnetic resonance imaging apparatus for taking a tomographic image of a subject mounted on a bed and a movable peripheral device means provided around the bed. Or, it is provided in the vicinity of or both of them. The sensor means is, for example, a magnetic sensor means for detecting a magnetic field that changes depending on a relatively approaching object or an object detecting means for detecting a distance to the relatively approaching object. Based on the information detected by these sensor means, the display means displays a warning when a change in the magnetic field of a predetermined value or more is detected or when an object approaching within a certain value is detected. By providing such a sensor means in the vicinity of the magnetic resonance imaging apparatus, peripheral equipment means, or the like, a dangerous state due to a leakage magnetic field of the magnetic resonance imaging apparatus is avoided.

A magnetic resonance imaging apparatus according to an eighteenth aspect is the magnetic resonance imaging apparatus according to the seventeenth aspect, wherein the magnetic resonance imaging apparatus includes a moving means and controls the moving means based on the information detected by the sensor means. It is equipped with. This is to prevent a dangerous state due to a leakage magnetic field of the magnetic resonance imaging apparatus by displaying a warning of a dangerous state and stopping or moving the movement of the magnetic resonance imaging apparatus.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a magnetic resonance imaging apparatus and a safety system for a magnetic resonance imaging apparatus according to the present invention will be described below with reference to the accompanying drawings. FIG. 2 is a block diagram showing the overall configuration of the magnetic resonance imaging apparatus according to the present invention. This magnetic resonance imaging apparatus, as shown in the figure, has a central processing unit (CP).
U) 1, sequencer 2, transmission system 3, magnetic field generation system 4
The receiving system 5, the signal processing system 6, the motor 23, the stopping means 24, and the sensor 25.

The CPU 1 controls each of the sequencer 2, the transmission system 3, the reception system 5, the signal processing system 6, the motor 23, and the stopping means 24 according to a predetermined program. The sequencer 2 operates based on a control command from the CPU 1 and outputs various commands necessary for collecting tomographic image data of the subject 7 to the transmission system 3, the magnetic field generation system 4, and the reception system 5. The sequencer 2 is a control unit that repeatedly applies a high-frequency magnetic field pulse that causes nuclear magnetic resonance to the atomic nuclei of the atoms forming the biological tissue of the subject 7 in a predetermined pulse sequence, and operates under the control of the CPU 1. Various commands necessary for collecting tomographic image data of the subject 7 are output to the transmission system 3, the magnetic field generation system 4, and the reception system 5.

The transmission system 3 uses a high frequency magnetic field pulse sent from the sequencer 2 to generate a high frequency pulse for causing a nuclear magnetic resonance in the atomic nuclei of the atoms forming the living tissue of the subject (not shown). The irradiation is performed repeatedly in a pulse sequence, and has a high frequency oscillator 8, a modulator 9 and an irradiation coil 11 as a high frequency coil.
The transmission system 3 amplitude-modulates the high-frequency pulse output from the high-frequency oscillator 8 by the modulator 9 based on the command from the sequencer 2, and the high-frequency pulse thus amplitude-modulated is supplied to the high-frequency amplifier 1
After being amplified by 0, it is supplied to the irradiation coil 11 arranged close to the subject to irradiate the subject with a predetermined pulsed electromagnetic wave.

The magnetic field generating system 4 is for generating a uniform static magnetic field around the subject in the body axis direction or in a direction orthogonal to the body axis, and is a permanent magnet in a space having a certain extent around the subject. It has a magnet type, normal conducting type or superconducting type static magnetic field generating magnet (not shown). Inside the static magnetic field generating magnet, in addition to the irradiation coil 11, a gradient magnetic field coil 13 for generating a gradient magnetic field and a receiving coil 14 of the receiving system 5 are installed. Gradient magnetic field generation system 22
Is a gradient magnetic field coil 13 having a configuration capable of independently applying a slice direction gradient magnetic field, a phase direction gradient magnetic field, and a frequency direction gradient magnetic field to a subject independently in mutually orthogonal Cartesian coordinate axis directions, and a gradient magnetic field for supplying a current to the gradient magnetic field coil. It is composed of a power supply 12. The gradient magnetic field power supply 12 is
It is controlled by the sequencer 2. By applying this gradient magnetic field, the slice plane for the subject can be set.

The receiving system 5 is an echo signal (NMR signal) emitted by nuclear magnetic resonance of atomic nuclei of the living tissue of the subject.
For detecting a high frequency coil, an amplifier 15 for amplifying a signal received by the receiving coil 14, a quadrature phase detector 16, and an A /
And a D converter 17. When the receiving system 5 detects the electromagnetic wave (NMR signal) generated from the subject 7 by the electromagnetic wave emitted from the transmitting side irradiation coil 11 by the receiving coil 14 arranged close to the subject, the signal is amplified. 15, converted into a predetermined digital amount through the quadrature detector 16 and the A / D converter 17, and converted into two series of collected data sampled by the quadrature detector 16 at the timing instructed by the sequencer 2. And sends it to the CPU 1.

The signal processing system 6 includes a CPU 1, an external storage device such as the magnetic disk 20 and the optical disk 19, and a CRT.
And a setting switch 21 for setting various states. The signal processing system 6 is a signal intensity distribution of an arbitrary cross section or a plurality of signals obtained as a result based on the signal processing such as Fourier transform, correction coefficient calculation, etc. executed by the CPU 1 to which the dedacil data from the receiving system 5 is input, image reconstruction, etc. The distribution obtained by performing an appropriate calculation on the signal is displayed as a tomographic image on the display 18 and recorded on the magnetic disk 20 or the optical disk 19 of the external storage device. Setting switch 21
Is to drive the motor 23 and the stopping means 24 to position the magnetic resonance imaging apparatus at a desired position in the operating room. The sensor 25 is a magnetic field detecting means and is composed of a Gauss meter (Hall probe), a magnetoresistive element, a magnetic diode, or the like. In a Gauss meter, when a current is passed through the meter and a magnetic field is applied in the direction perpendicular to the direction of the current, a voltage proportional to the strength of the magnetic field is generated in the direction in which the current flows and the direction perpendicular to the direction of the magnetic field. Therefore, the magnitude of the magnetic field is measured by detecting the voltage generated at this time. Since the electric resistance of the magnetoresistive element changes in proportion to the strength of the applied magnetic field, the magnitude of the magnetic field is measured based on the changed voltage. Since the current-voltage characteristics of the magnetic diode change depending on the strength of the applied magnetic field, the magnitude of the magnetic field is measured based on the voltage at this time.

Next, an outline of a safety system for an operating room equipped with the magnetic resonance imaging apparatus according to the first embodiment will be described with reference to FIGS. FIG. 3 is a diagram schematically showing a state in the operating room related to the safety system for the operating room including the magnetic resonance imaging apparatus according to the first embodiment. FIG. 4 is a side view of the operating room in FIG. 3 as seen from the lateral direction. 3 and 4, the magnetic resonance imaging apparatus 30 has a leakage magnetic field 30a generated around the magnetic resonance imaging apparatus 30. In the figure, about 5 Gauss lines are indicated by dotted lines.
A patient 101, which is a subject, lies on a bed 102. The head of the patient 101 is fixed to the surgical unit fixing tool 103. The vicinity of the surgical unit fixing tool 103 is called a surgical field 104. Peripheral devices 105 to 107 such as a drip, an electrocardiograph, and a surgical microscope are provided around the patient 101 (bed 102). In addition, a surgical instrument table 109 having a surgical instrument 108 mounted thereon is provided near the surgical unit fixing tool 103. The operator 110 uses these peripheral devices 105 to 107.
And surgery is performed using the surgical instrument 108. When performing an operation, as shown in FIGS. 3 and 4, the magnetic resonance imaging apparatus 30 includes a surgical field 104, peripheral devices 105 to 107, and a surgical instrument table 109 within a 5 Gauss line of the leakage magnetic field 30a.
It has been moved and retracted to a position where it cannot enter. In addition,
In FIG. 4, the peripheral devices 105 and 106 and the surgical instrument 108 of FIG. 3 are not shown.

The magnetic resonance imaging apparatus 30 according to this embodiment includes a sensor 25, a comparing means 1a, and a moving means 3.
1 and stop means 24. The sensor 25 is a magnetic field detecting means such as a Gauss meter (Hall probe), a magnetoresistive element, or a magnetic diode as described above, and a magnetic body (peripheral devices 105 to 107, surgical instrument) that relatively approaches the magnetic resonance imaging apparatus 30. 108, the surgical instrument table 109, etc.) outputs a voltage value corresponding to the magnetic field changed. The comparison means 1a compares the voltage value corresponding to the amount of change in the magnetic field output from the sensor 25 with a predetermined reference value, and determines whether or not it exceeds the reference value. The processing is executed by the CPU 1. When it is determined that the voltage value exceeds the reference value, the comparison unit 1a outputs a stop signal to the stop unit 24 to stop the operation of the moving unit 31 and stop the movement of the magnetic resonance imaging apparatus 30.

Since the leakage magnetic field 30a is stronger as it approaches the magnetic resonance imaging apparatus 30, the sensor 25 has
In addition to the magnetic field detection means, an obstacle detection sensor that can measure the distance to an object and detect an object approaching a certain distance is provided. That is, the magnetic resonance imaging apparatus 30 according to this embodiment includes the moving unit 3
Since it is possible to move freely in the operating room by means of 1, there is provided a detection sensor for detecting an obstacle during the movement. The obstacle detection sensor is composed of a conventionally known ultrasonic sensor, photoelectric sensor, infrared sensor, or the like. The ultrasonic sensor emits ultrasonic waves and measures the distance to an object based on the reflected waves. The photoelectric sensor irradiates laser light and measures the distance to an object based on the reflected light. The infrared sensor irradiates infrared rays and measures the distance to an object based on the reflected light. It should be noted that there are various sensors other than this, and they may be used. When the distance to the object detected by the obstacle detection sensor approaches the comparing means 1a exceeding a predetermined reference value, the leakage magnetic field 30a may exert a great influence on the object. Similarly, a stop signal is output to the stop means 24, the operation of the moving means 31 is stopped, and the operation of the magnetic resonance imaging apparatus 30 is stopped. In addition,
For the bed 102 that is not affected by the leakage magnetic field and is known to approach as the magnetic resonance imaging apparatus 30 moves, detection as an obstacle may be excluded in advance. Good.

5 and 6 are views showing specific examples of the moving means and the stopping means of the magnetic resonance imaging apparatus of FIG. In FIG. 5A, the moving means 31 is composed of wheels 31 a and the like provided on the magnetic resonance imaging apparatus 30. The stopping means 24 is composed of a disc brake or a drum brake 24a that stops the rotation of the wheels 31a. The comparison means 1a outputs a stop signal to the disc brake or the drum brake 24a to stop the rotation of the wheels 31a.

In FIG. 5 (b), the moving means 31 is a wheel 31a provided on the magnetic resonance imaging apparatus and a wheel shaft gear 31c provided on a wheel shaft 31b of the wheel 31a.
And a rotary shaft gear 31d meshed with the wheel shaft gear 31c, and a motor 23 for rotationally driving the rotary shaft 31e. The stopping means 24 is composed of an electromagnetic brake 24b provided at the other end of the rotating shaft 31e. The comparison means 1a uses the electromagnetic brake 24b and / or the motor 2
3, a stop signal is output, the power to the electromagnetic brake 24b and / or the motor 23 is cut off, and the rotation of the wheels 31a is stopped.

In FIG. 6A, the moving means 31 is composed of a rail 60 provided on the floor surface, and the magnetic resonance imaging apparatus 30 moves along the rail 60. Although the relationship between the magnetic resonance imaging apparatus 30 and the rail 60 is not shown, it may be configured as a monorail or may be in contact with the floor surface via wheels. The stopping unit 24 connects the stopper 61 to the upper surface of the rail 60 by using the attractive force or repulsive force of the electromagnet 62, and stops the movement of the magnetic resonance imaging apparatus 30 by the frictional force between the stopper 61 and the rail 60. It is a thing. On the contrary, the stopping operation is released by the electromagnet 62 separating the stopper 61 from the rail 60. The comparison means 1a outputs a stop signal to the electromagnet 61, connects the stopper 61 to the rail 60, and stops the movement of the magnetic resonance imaging apparatus 30.

In FIG. 6B, the moving means 31 is a wheel 31a provided on the magnetic resonance imaging apparatus and a wheel shaft gear 31c provided on a wheel shaft 31b of the wheel 31a.
And a reverse gear 31g and a forward gear 31h meshed with the wheel shaft gear 31c, and a motor 23 that rotationally drives the wheel shaft 31b via the reverse gear 31g or the forward gear 31h and the wheel shaft gear 31c. Composed. The stopping means 24 is composed of a disc brake or a drum brake 24a for stopping the rotation of the wheels 31a as in FIG. 5 (a). The comparison means 1a outputs a stop signal to the disc brake or the drum brake 24a, and the wheel 31
Stop the rotation of a. After that, the comparison unit 1a changes the gears so that the reverse gear 31g and the wheel shaft gear 31c mesh with each other, releases the stop, and retracts (retracts) the magnetic resonance imaging apparatus until the reference value is reached. In addition,
As the stopping means 24, instead of the disc brake or the drum brake 24a, the electromagnetic brake 24b of FIG. 5B is used.
May be provided on the rotating shaft of the motor. Also, the reverse gear 3
Instead of the 1g and the forward gear 31h, an inverter motor may be used as the motor 31j to control the rotation direction of the motor to control the forward and backward movements of the magnetic resonance imaging apparatus.

FIG. 7 is a block diagram showing a schematic configuration of a safety system in an operating room equipped with the magnetic resonance imaging apparatus of FIG. FIG. 8 is a flowchart showing an operation example of a safety system for an operating room equipped with the magnetic resonance imaging apparatus of FIG. The operation of this safety system will be described below with reference to FIGS. 7 and 8.

In step S81, the magnetic resonance imaging apparatus 30 is moved to the inspection position. In the case of only the wheels of FIG. 5 (a), the operator pushes and moves the wheels, and FIG.
Alternatively, in the case of driving the motor shown in FIG. 6B, the motor is used for movement. At this time, the comparison unit 1a outputs a release signal to the stop unit 24, and the stop of the moving unit 31 is released.

In step S82, the sensor 25 constantly responds to a magnetic field change, that is, a magnetic field changed by a magnetic body (peripheral devices 105 to 107, surgical instrument 108, surgical instrument table 109, etc.) that relatively approaches the magnetic resonance imaging apparatus 30. The detected voltage value is detected, and the relative distance between the magnetic resonance imaging apparatus 30 and an object (obstacle) that is close to a certain distance is detected, and the relative distance is detected.
Supply to.

In step S83, the comparison means 1a successively compares the measured values (voltage value corresponding to the change in the magnetic field and voltage value corresponding to the relative distance to the obstacle) supplied from the sensor 25 with the reference value, and these values are compared. It is determined whether or not the measured value is larger than the reference value. If it is determined to be larger (yes), the process proceeds to the next step S84, and if it is determined to be less than or equal to the reference value (no), the process jumps to step S88. .

In step S84, it is determined in step S83 that at least one of the measured value, that is, the voltage value corresponding to the change in the magnetic field and the voltage value corresponding to the relative distance to the obstacle is larger than the reference value. Stop means 24
Output to. Upon receiving the stop signal, the stopping means 24 executes the stopping operation of the moving means 31. Figure 5 shows the stopping operation.
(A) disc brake or drum brake 24a,
This is performed by the electromagnetic brake 24b of FIG. 5 (b) and the stopper 61 of FIG. 6 (a).

The fact that the magnetic resonance imaging apparatus 30 has stopped means that a magnetic material (peripheral devices 105 to 107, surgical instrument 108, surgical instrument table 109, etc.) or some obstacle has approached, so in step S85,
These objects and the like are retracted from the periphery of the magnetic resonance imaging apparatus 30.

In step S86, as in step S83, it is determined whether or not the measured value is larger than the reference value. If it is determined to be larger (yes), step S8 is performed.
Returning to step 5, if it is determined that the value is not more than the reference value (no), the process proceeds to step S87. This is to determine whether or not the measured value has become equal to or less than the reference value due to the evacuation of the object or the like.

In step S87, it is determined in step S87 that the measured value, that is, the voltage value corresponding to the change in the magnetic field and the voltage value corresponding to the relative distance to the obstacle are below the reference value. Output to the stop means 24. The stopping means 24 that has received the cancellation signal cancels the stopping operation of the moving means 31.

In step S88, it is determined whether or not the magnetic resonance imaging apparatus 30 has moved to the predetermined inspection position. If the movement has not been completed, step S88 is performed.
Returning to step 82, if the movement is completed, step S
Proceed to 89.

In step S89, a stop signal is output to the stop means 24 to end the movement of the magnetic resonance imaging apparatus 30. The stopping operation is similar to step S84 in FIG.
(A) disc brake or drum brake 24a,
This is performed by the electromagnetic brake 24b of FIG. 5B and the stopper 61 of FIG. 6A. The above operation has been described with respect to the case where the magnetic resonance imaging apparatus 30 moves to the inspection position. However, when the magnetic resonance imaging apparatus 30 returns to the original position after the inspection, the magnetic resonance imaging apparatus 30 moves while performing the detection processing of the magnetic substance and the obstacles in the same manner. It will be. Furthermore, the magnetic resonance imaging apparatus 3
When 0 is equipped with the moving mechanism as shown in FIG. 6B, the magnetic resonance imaging apparatus 30 may be retracted so that the determination result of step S86 becomes no along with the stop operation.

Next, an operating room safety system equipped with the magnetic resonance imaging apparatus of the present invention according to the second embodiment will be explained. FIG. 9 is a diagram schematically showing a state in the operating room related to the safety system of the operating room including the magnetic resonance imaging apparatus according to the second embodiment. 10 and 11 are side views of the operating room of FIG. 9 as seen from the lateral direction, FIG. 10 illustrates the positional relationship of the sensors, and FIG. 11 illustrates the positional relationship of the warning display means. . 9 to 11, the same components as those in FIGS. 3 and 4 are designated by the same reference numerals, and the description thereof will be omitted. The second embodiment is different from the first embodiment in that the peripheral devices 105 to 107 in which the sensor serving as the magnetic field detecting means is a magnetic body, the surgical instrument 108, and the surgical instrument table 1 are used.
It is provided on the 09 side and further informs the operator (operator, nurse, etc.) in the operating room that a magnetic material has approached the magnetic resonance imaging apparatus 30 and an obstacle has approached by using a warning display means. This is the point. In addition,
10 and 11, the peripheral devices 105 and 10 of FIG.
6, the surgical instrument 108 and the sensors 91, 92 are not shown.

Peripheral devices 105 to 105 according to the second embodiment
The surgical instrument table 107 and the surgical instrument table 109 include sensors 91 to 94, and the magnetic resonance imaging apparatus 30 includes the comparison unit 1
a, moving means 31 and stopping means 24. The sensors 91 to 94 are magnetic field detecting means such as a Gauss meter (Hall probe), a magnetoresistive element or a magnetic diode as in the first embodiment, and correspond to a leakage magnetic field from the magnetic resonance imaging apparatus 30 which is relatively close. The output voltage value is output to the comparison means 1a. Comparison means 1a
Is for comparing the voltage value corresponding to the leakage magnetic field output from these sensors 91 to 94 with a predetermined reference value to determine whether or not it exceeds the reference value. The processing is executed by the CPU 1. Here, the predetermined reference value is determined in consideration of the peripheral devices 105 to 107 to which the sensors 91 to 94 are attached, the components of the surgical instrument table 109 (presence or absence of a magnetic body, etc.), the weight thereof, the fixing method, and the like. What was done is set. As a result, it is possible to accurately determine whether or not each of the peripheral devices 105 to 107 and the surgical instrument table 109 is within the safe leakage magnetic field range. When the comparison unit 1a determines that the voltage value exceeds the reference value, it outputs a stop signal to the stop unit 24 to stop the operation of the moving unit 31, and the magnetic resonance imaging apparatus 30.
And the warning display means as shown in FIG. 11 displays a warning that the leakage magnetic field exceeds the reference value.
It should be noted that these sensors 91 to 94 do not include an obstacle detection sensor capable of detecting an object approaching a certain fixed distance as in the first embodiment. Therefore, the magnetic resonance imaging apparatus 30 may be provided with a detection sensor for detecting an obstacle during movement as in the first embodiment, and magnetic field detection means other than the obstacle detection sensor. Needless to say, it may be provided.

The warning display means includes warning lights 111 to 114,
It is composed of a head-mounted monitor 115, a monitoring monitor 116, a warning sound speaker 117, and the like. Warning lights 111-114
Are provided adjacent to the sensors 91 to 94. Although not shown, the warning lights 111 and 112 are provided adjacent to the sensors 91 and 92.
The warning lights 111 to 114 are turned on or blinked when the comparison unit determines that the detection voltage of the adjacent sensors 91 to 94 exceeds the reference value. Therefore, which sensor 91
It is possible to see at a glance whether or not .about.94 has penetrated into the leakage magnetic field larger than the reference value.

The head-mounted monitor 115 is called a head mounted display, and is a see-through type display mounted on the head of an operator or the like, and a detection means as a pointing device for detecting the line-of-sight position of a doctor or the like. It is equipped with an eye sensor mechanism and a microphone as keyboard input means, and the voice from the microphone is converted into character information by voice recognition technology. This see-through type head mounted display is known in the technical field of virtual reality, and is externally shaped like a spectacle or helmet and is worn on the head of a doctor or the like. The head mounted display used in this embodiment has a part in the front direction of the line of sight, for example, the lower half covered with a transparent cover or lens to enable a front view. A display device such as a small liquid crystal display is arranged in the section (for example, the upper side),
An image can be displayed by receiving a video signal from the display control device. The details of the head mounted display device are described in JP-A-8-206083.
The description is omitted here because it is described in Japanese Patent Publication.
The monitor 116 is a normal image display device, and is provided at a position such as the ceiling of an operating room where it is easy to see. This head-mounted monitor 1115 and / or monitoring monitor 116
Which sensor 91 to 9 is used when the comparison unit determines that the detected voltage of the sensor 91 to 94 exceeds the reference value.
The images of the peripheral devices 105 to 107 and the surgical instrument table 109 are displayed and warned so that it can be seen at a glance whether 4 is invading into the leakage magnetic field larger than the reference value. The name of the peripheral device may be displayed in addition to the video of the peripheral device.

The warning sound speaker 117 sounds a prerecorded voice message. The voice message includes information about the peripheral devices 105 to 107 and the name and place of the surgical instrument table 109 so that it can be seen which sensor 91 to 94 is intruding into the leakage magnetic field larger than the reference value. ing. The head-mounted monitor 11
When the earphone is provided in 5, the same voice message is also pronounced and notified to the earphone. Note that a warning buzzer or the like may be pronounced instead of or at the same time as the voice message. Further, the warning lights 111 to 114 provided adjacent to the sensors 91 to 94 may emit a warning buzzer at the same time when they are turned on and blink. This makes it possible to easily recognize which sensor is invading the leakage magnetic field.

FIG. 12 is a block diagram showing a schematic configuration of a safety system in an operating room equipped with the magnetic resonance imaging apparatus of FIGS. 9 to 11. FIG. 13 is a flowchart showing an operation example of the safety system in the operating room equipped with the magnetic resonance imaging apparatus of FIGS. The operation of this safety system will be described below with reference to FIGS. 12 and 13.

In step S131, the magnetic resonance imaging apparatus 30 is moved to the inspection position. Step S1
In 32, each of the sensors 91 to 94 constantly detects a magnetic field change, that is, a voltage value corresponding to a leakage magnetic field changed due to the approach of the magnetic resonance imaging apparatus 30, and compares the detected voltage value.
supply to a. In step S133, the comparison unit 1a sequentially compares the measured values (voltage values corresponding to changes in the leakage magnetic field) supplied from the sensors 91 to 94 with respective reference values, and these measured values are larger than the reference values. It is determined whether or not it is large (yes), the process proceeds to the next step S134, and if it is determined that it is less than or equal to the reference value (no), the process jumps to step S138.

In step S134, it is determined in step S133 that the measured value, that is, the voltage value corresponding to the change in the leakage magnetic field is larger than the reference value.
~ 117 to give a warning and stop signal to stop means 2
Output to 4. Upon receiving the stop signal, the stopping means 24 executes the stopping operation of the moving means 31. Warning display means 111
~ 117 that a warning is issued and the magnetic resonance imaging apparatus 30 is stopped means that the peripheral devices 105 to 10
7. This means that the surgical instrument 108, the surgical instrument table 109, and the like have entered the leak magnetic field, and therefore, in step S135, peripheral devices that are considered to have entered are retracted from the leak magnetic field of the magnetic resonance imaging apparatus 30.

In step S136, step S133
Similarly, it is determined whether or not the measured value is larger than the reference value, and if it is determined to be larger (yes), step S
Returning to step 135, if it is determined that the value is not more than the reference value (no), the process proceeds to step S137. This is to determine whether or not the measured value has become less than or equal to the reference value due to the evacuation of peripheral devices and the like.

In step S137, since it is determined in step S137 that the measured value, that is, the voltage value corresponding to the leakage magnetic field is equal to or less than the reference value, the stop operation cancel signal is output to the stopping means 24. The stopping means 24 that has received the cancellation signal cancels the stopping operation of the moving means 31.

In step S138, it is determined whether or not the magnetic resonance imaging apparatus 30 has moved to the predetermined inspection position. If the movement has not been completed, the process returns to step S132 to complete the movement. In this case, the process proceeds to step S139.

In step S139, a stop signal is output to the stop means 24 to end the movement of the magnetic resonance imaging apparatus 30. The above operation has been described with respect to the case where the magnetic resonance imaging apparatus 30 moves to the inspection position. However, when the magnetic resonance imaging apparatus 30 returns to the original position after the inspection is completed, similarly, it is detected whether or not the peripheral device enters the leakage magnetic field. Will move while doing. If the magnetic resonance imaging apparatus 30 includes a moving mechanism as shown in FIG. 6B, the magnetic resonance imaging apparatus 3 is set so that the determination result of step S136 becomes no together with the stop operation.
You may set 0 back.

Next, an operating room safety system equipped with the magnetic resonance imaging apparatus of the present invention according to the third embodiment will be explained. FIG. 14 is a diagram schematically showing a state in the operating room related to the safety system for the operating room including the magnetic resonance imaging apparatus according to the third embodiment, and is a side view of the operating room seen from the lateral direction. . In FIG. 14, the same components as those in FIG. 11 are designated by the same reference numerals, and the description thereof will be omitted. This third embodiment is the first
The difference from the second embodiment is that sensors 141 to 148 that are magnetic field detection means and warning lights 151 to 157 that are warning display means are provided on the floor and ceiling. Note that, in FIG. 14, the peripheral devices 105 and 106 and the surgical instrument 108 are not shown.

The sensors 141 to 148 are magnetic field detecting means such as a Gauss meter (Hall probe), a magnetoresistive element or a magnetic diode, which are the same as those in the first and second embodiments, and are relatively close to each other. The voltage value corresponding to the leakage magnetic field from is output to the comparison means 1b and 1c. The sensors 141 to 144 and the warning lights 151 to 154 are both hung on the ceiling. The sensors 141 to 144 and the warning lights 151 to 154 are provided adjacent to each other at substantially the same position. The comparison means 1b compares the voltage values output from these sensors 141 to 144 with a predetermined reference value and determines whether or not it exceeds the reference value. The CPU 1 of FIG. The processing is executed. When it is determined that the voltage value exceeds the reference value, the comparison unit 1b turns on or blinks the warning lights 151 to 154. When any of the warning lights 151 to 154 is turned on or blinks, it can be easily recognized that the vicinity thereof has entered the leakage magnetic field. Therefore, the peripheral device 1 is provided below the illuminated or blinking warning lights 151 to 154.
05-107, the safety can be ensured by eliminating the surgical instrument base 109.

On the other hand, the sensors 145 to 148 and the warning light 1
55 to 15b are both provided on the floor. Sensor 14
5 to 148 and the warning lights 155 to 158 are provided adjacent to each other at substantially the same position, the warning light 159 is substantially at an intermediate point between the sensor 145 and the sensor 146, and the warning light 15a is the sensor 1.
46 and the sensor 147 are provided at approximately the midpoint, and the warning light 15b is provided at approximately the midpoint between the sensors 147 and 148, respectively. The comparison means 1c uses these sensors 144.
~ 148 compares the voltage value output from the predetermined reference value, determines whether or not it exceeds the reference value, and estimates the magnetic field strength in the vicinity of the warning lights 159 to 15b. The CPU 1 of 2 executes the processing.
As shown in the leakage magnetic field distribution of FIG. 15, the leakage magnetic field distribution of the magnetic resonance imaging apparatus 30 is measured in advance, and the distance between the sensors 145 to 148 and the magnetic resonance imaging apparatus 30 is set to the obstacle of the first embodiment. Measurement is performed using the detection sensor 25, the magnetic field strength in the vicinity of the warning lights 159 to 15b is estimated based on the distance and the measurement values of the sensors 145 to 148, the estimated value is compared with the reference value, and the estimated value is By determining whether or not the reference value is exceeded, the warning light 15
Lighting or blinking of 9 to 15b is controlled. By thus estimating the magnetic field strength, it is possible to reduce the number of sensors. If any of the warning lights 155 to 15b is turned on or blinks, it can be easily recognized that the vicinity thereof has entered the leak magnetic field. Therefore, the safety can be ensured by preventing the peripheral devices 105 to 107 and the surgical instrument table 109 from being present above the lit or blinking warning lights 155 to 15b. By installing the sensors on the ceiling side and the sensors on the floor side at different positions, it is possible to accurately detect the leakage magnetic field. Although the case where the warning lights 151 to 15b are turned on or blinked has been described, a warning including the head-mounted monitor 115, the monitoring monitor 116, the warning sound speaker 117, and the like, as in the case of the second embodiment. You may give a warning using a display means.

FIG. 16 is a block diagram showing a schematic configuration of a safety system in an operating room equipped with the magnetic resonance imaging apparatus of FIG. FIG. 17 is a flowchart showing an operation example of a safety system in an operating room equipped with the magnetic resonance imaging apparatus of FIG. The operation of this safety system will be described below with reference to FIGS. 16 and 17.

In step S171, each sensor 141-
148 constantly detects the voltage value corresponding to the magnetic field change, that is, the leakage magnetic field changed by the approach of the magnetic resonance imaging apparatus 30, and supplies it to the comparison means 1b, 1c. In step S172, the comparison means 1b and 1c cause each sensor 1
The measured values (voltage values corresponding to changes in the leakage magnetic field) and estimated values supplied from 41 to 148 are sequentially compared with respective reference values, and whether these measured values and estimated values are larger than the reference value or not. If it is determined that it is larger (yes), the process proceeds to the next step S173, and is equal to or less than the reference value (n
If it is determined as o), the process proceeds to step S175.

In step S173, since it is determined in step S172 that the measured value, that is, the voltage value and the estimated value corresponding to the change in the leakage magnetic field are larger than the reference value, the warning display means 151 to 15b and 115 to 117 are used to issue a warning. To do. Since warnings have been issued from the warning display means 151 to 15b and 115 to 117, in step S174, it is confirmed whether or not the peripheral devices 105 to 107, the surgical instrument 108, the surgical instrument table 109, etc. are present at the position where the warning is issued. If they exist, they are evacuated to a place that is not affected by the leakage magnetic field of the magnetic resonance imaging apparatus 30,
The process ends. In step S175, it is determined in step S172 that the measured value, that is, the voltage value and the estimated value corresponding to the change in the leakage magnetic field are equal to or less than the reference value. Therefore, the warning display of the warning display means 151 to 15b, 115 to 117 is canceled, The process ends. If the magnetic resonance imaging apparatus 30 includes a moving mechanism as shown in FIG. 6B, a warning is given and a stop operation is performed, and the determination process similar to step S172 is performed. n
The magnetic resonance imaging apparatus 30 may be retracted so that it becomes o. As described above, according to the third embodiment, it is possible to know a dangerous range when a ferromagnetic material is brought in. Therefore, an operator, an operator of the magnetic resonance imaging apparatus, or the like can visually check the warning display means. It is possible to avoid suction in advance by moving surgical tools and peripheral devices.

Next, an operating room safety system equipped with the magnetic resonance imaging apparatus of the present invention according to the fourth embodiment will be explained. FIG. 18 is a diagram showing an outline of a state in the operating room related to the safety system for the operating room including the magnetic resonance imaging apparatus according to the fourth embodiment, and is a side view of the operating room seen from the lateral direction. . FIG. 19 is a block diagram showing a schematic configuration of a safety system in an operating room equipped with the magnetic resonance imaging apparatus of FIG. In FIG.
Since the same components as those in FIG. 11 or FIG. 14 are designated by the same reference numerals, the description thereof will be omitted. The difference between the fourth embodiment and the first to third embodiments is that a sensor 181 is provided in the surgical field 104 near the surgical unit fixing tool 103, and further, the surgical operation is performed. Operator (operator) 11
0 is provided with sensors 182 to 184.
In the figure, both cases are shown, but it goes without saying that they may be provided separately. Sensor 182
Is the head mounted monitor 115, and the sensor 183 is the operator 110.
The sensor 184 is attached to each of the belts and the wrists of the operator, but the operator (operator) 110 may have at least one sensor. Note that, in FIG. 14, the peripheral devices 105 and 106 and the surgical instrument 108 are not shown.

The sensors 181 to 184 are magnetic field detecting means such as a Gauss meter (Hall probe), a magnetoresistive element or a magnetic diode as in the first to third embodiments, and the magnetic resonance imaging apparatus 30 is relatively close to each other. The voltage value corresponding to the leakage magnetic field from is output to the comparison means 1d. Since the sensors 182 to 184 are portable, it is assumed that the comparison means is built in near each sensor unit. Each sensor 181-184 has a warning light 185-
188 are provided adjacent to each other. Therefore, the comparison means 1
d and the comparison means built in the sensors 182-184,
The voltage values output from these sensors 181 to 184 are compared with a predetermined reference value to determine whether or not it exceeds the reference value. Each comparing means turns on or blinks the warning lights 185 to 188 when it is determined that the voltage value exceeds the reference value. When any of the warning lights 185 to 188 is turned on or blinks, it can be easily recognized that the vicinity thereof has entered the leak magnetic field. That is, it is possible to easily measure the magnetic field strength in the operative field, and whether the magnetic field in the operative field is below a reference value before surgery, that is, it is safe to bring a surgical instrument that is a ferromagnetic material into the operative field. Whether or not it can be easily confirmed. In addition, the magnetic field strength around the sensor wearer can be easily measured during surgery and during imaging, and it is easy to determine whether it is safe to bring in a surgical instrument that is a ferromagnetic body before surgery. You can check.

FIG. 19 is a block diagram showing a schematic configuration of a safety system for an operating room equipped with the magnetic resonance imaging apparatus of FIG. 18, and FIG. 19A is a surgical field 104 near the surgical unit fixing tool 103. 19B corresponds to the sensors 181 provided inside, and FIG. 19B corresponds to the sensors 182 to 184 provided on the head, waist, arms, etc. of the operator 100. A flowchart showing an operation example of the safety system in the operating room equipped with this magnetic resonance imaging apparatus is the same as that in FIG. 17 described above.

That is, in step S171, the sensors 181 to 184 constantly detect the voltage value corresponding to the magnetic field change, that is, the leakage magnetic field changed due to the approach of the magnetic resonance imaging apparatus 30, and the detected voltage value is compared with the comparison means 1d and the sensors 182 to 184. Supply to the comparison means built in. In step S172, the comparison unit 1d and the sensors 182-1 are connected.
The comparison means built in 84 sequentially compares the measured values (voltage values corresponding to changes in the leakage magnetic field) supplied from the sensors 181 to 184 with respective reference values, and these measured values are larger than the reference values. It is judged whether or not it is larger (y
If it is determined to be es), the process proceeds to the next step S173, and if it is determined to be less than or equal to the reference value (no), step S173.
Proceed to 175.

In step S173, it is determined in step S172 that the measured value, that is, the voltage value corresponding to the change in the leakage magnetic field is larger than the reference value. Therefore, the warning display means 185 is displayed.
~ 188 to warn. Warning display means 185-18
Since a warning was issued from 8, in step S174,
It is confirmed whether or not the peripheral devices 105 to 107, the surgical instrument 108, the surgical instrument table 109, etc. are present at the position where the warning is issued, and if they are present, they are not affected by the leakage magnetic field of the magnetic resonance imaging apparatus 30. Evacuate to a place and finish the process. In step S175, it is determined in step S172 that the measured value, that is, the voltage value corresponding to the change in the leakage magnetic field is equal to or less than the reference value. Therefore, the warning displays of the warning display units 185 to 188 are canceled, and the process ends. The magnetic resonance imaging apparatus 30 is shown in FIG.
When a moving mechanism such as the above is provided, a warning is given and a stop operation is performed, and further, the same determination processing as in step S172 is performed, and the magnetic resonance imaging apparatus 30 is retracted so that the determination result is no. May be.

Although the case where the warning lights 185 to 188 are turned on or blinked has been described, as in the case of the second or third embodiment, the head-mounted monitor 115, the monitoring monitor 116, and the warning sound speaker 117. The warning may be given by using a warning display means including the above. Further, in the case of the above-described embodiment, the sensor power supply in the operative field or the sensor power supply in the vicinity of the magnetic resonance imaging apparatus is cut off during imaging by the magnetic resonance imaging apparatus. By doing so, the adverse effect of noise from the sensor on the captured image can be reduced.

Further, in the above-mentioned embodiment, the first to fourth
However, it is needless to say that these embodiments may be combined in various ways to form a safety system for an operating room having a magnetic resonance imaging apparatus. Further, although not mentioned in the above-mentioned embodiment, a fixing band for fixing the surgical instrument may be provided on the surgical instrument table 109 so that the surgical instrument is not sucked by the leakage magnetic field of the magnetic resonance imaging apparatus. Further, a magnet for fixing the surgical instrument may be provided on the surgical instrument table 109. Further, the surgical instrument base 109 may be covered with a magnetic shield member so that the influence of the leakage magnetic field does not affect the surgical instrument. In the above-described embodiment, the case where the magnetic resonance imaging apparatus moves laterally in the operating room has been described, but the same can be applied to the case where the magnetic resonance imaging apparatus moves vertically from the ceiling or floor.

[0075]

According to the present invention, it is possible to prevent an object, such as an instrument or peripheral equipment used for surgery, which is not preferable to approach the leak magnetic field generated by the magnetic resonance imaging apparatus from approaching the leak magnetic field. Can be

Further, according to the present invention, when an object which is not desirable to approach the leakage magnetic field generated by the magnetic resonance imaging apparatus such as an instrument or peripheral equipment used for surgery approaches the leakage magnetic field. But it can avoid the dangerous situation.

[Brief description of drawings]

FIG. 1 is a diagram showing a conventional schematic configuration when a magnetic resonance imaging apparatus is installed in an operating room and a non-percutaneous treatment is performed there.

FIG. 2 is a block diagram showing the overall configuration of a magnetic resonance imaging apparatus according to the present invention.

FIG. 3 is a diagram schematically showing a state in an operating room related to a safety system of the operating room including the magnetic resonance imaging apparatus according to the first embodiment.

FIG. 4 is a side view of the operating room of FIG. 3 as seen from the lateral direction.

5 is a diagram showing a specific example of moving means and stopping means of the magnetic resonance imaging apparatus of FIG.

FIG. 6 is a diagram showing a specific example of moving means and stopping means of the magnetic resonance imaging apparatus of FIG.

7 is a block diagram showing a schematic configuration of a safety system of an operating room including the magnetic resonance imaging apparatus of FIG.

8 is a flowchart showing an operation example of a safety system for an operating room including the magnetic resonance imaging apparatus of FIG.

FIG. 9 is a diagram schematically showing a state in an operating room related to a safety system for an operating room including a magnetic resonance imaging apparatus according to a second embodiment.

FIG. 10 is a side view showing the positional relationship of the sensors when the operating room in FIG. 9 is viewed from the lateral direction.

FIG. 11 is a view showing the arrangement relationship of warning display means when the operating room in FIG. 9 is viewed from the lateral direction.

FIG. 12 is a block diagram showing a schematic configuration of a safety system of an operating room including the magnetic resonance imaging apparatus of FIGS. 9 to 11.

FIG. 13 is a flowchart showing an operation example of a safety system in an operating room including the magnetic resonance imaging apparatus of FIGS. 9 to 11.

FIG. 14 is a diagram showing an outline of a state in an operating room related to a safety system of the operating room including the magnetic resonance imaging apparatus according to the third embodiment, and is a side view of the operating room as seen from a lateral direction. .

FIG. 15 is a diagram showing the relationship between the distance from the magnetic resonance imaging apparatus and the leakage magnetic field distribution.

16 is a block diagram showing a schematic configuration of a safety system of an operating room including the magnetic resonance imaging apparatus of FIG.

17 is a flowchart showing an operation example of a safety system in an operating room equipped with the magnetic resonance imaging apparatus of FIG.

FIG. 18 is a diagram showing an outline of a state in the operating room related to a safety system of the operating room including the magnetic resonance imaging apparatus according to the fourth embodiment, and is a side view of the operating room seen from the lateral direction. .

19 is a block diagram showing a schematic configuration of a safety system for an operating room including the magnetic resonance imaging apparatus of FIG.

[Explanation of symbols]

1 ... CPU, 1a-1d ... Comparing means, 2 ... Sequencer,
3 ... Transmission system, 4 ... Magnetic field generation system, 5 ... Reception system, 6 ... Signal processing system, 7, 101 ... Subject, 8 ... High frequency oscillator, 9 ... Modulator, 10 ... High frequency amplifier, 11 ... Irradiation coil, 12 ...
Gradient magnetic field power source, 13 ... Gradient magnetic field coil 14, Receiving coil, 15 ... Amplifier, 16 ... Quadrature phase detector, 17 ... A /
D converter, 18 ... Display, 19 ... Optical disk, 2
0 ... Magnetic disk, 21 ... Setting switch, 22 ... Gradient magnetic field generation system, 23 ... Motor, 24 ... Stop means, 24a ... Disk brake (drum brake), 25, 91-9
4, 141-148, 181-184 ... Sensor, 30,
100 ... Magnetic resonance imaging apparatus, 30a, 100a
... Leakage magnetic field, 31 ... Moving means, 31a ... Wheels, 101 ...
Subject, 102 ... Bed, 103 ... Surgery unit fixture, 104
... surgical field, 105-107 ... peripheral equipment, 108 ... surgical instrument, 109 ... surgical instrument table, 110 ... operator, 111-11
4, 151-15b, 185-188 ... Warning light, 115
... Head-mounted monitor, 116 ... Monitoring monitor, 117 ... Warning sound speaker

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hirotaka Takeshima             1-chome 1-14-1 Kanda, Chiyoda-ku, Tokyo             Inside the Hitachi Medical Co. (72) Inventor Kenji Sakakibara             1-chome 1-14-1 Kanda, Chiyoda-ku, Tokyo             Inside the Hitachi Medical Co. (72) Inventor Riki Suzuki             1-chome 1-14-1 Kanda, Chiyoda-ku, Tokyo             Inside the Hitachi Medical Co. F term (reference) 4C096 AA20 AB46 AD17 AD19 AD23                       DD20 EA06 EA10 EB04 FB03                       FC10 FC20

Claims (18)

[Claims] 1. A bed on which a subject is mounted, and a magnetic resonance imaging apparatus that moves in an imaging room to capture a tomographic image of the subject on the bed, in the vicinity of or near the magnetic resonance imaging apparatus. Magnetic sensor means for detecting a magnetic field that changes due to an object that is placed and relatively approaching, and a display means that displays a warning indicating that a change in the magnetic field of a predetermined value or more is detected by the magnetic sensor means. A magnetic resonance imaging apparatus comprising: 2. A bed on which a subject is mounted, and a magnetic resonance imaging apparatus which moves in an imaging chamber to capture a tomographic image of the subject on the bed, and peripheral device means movable around the bed. A magnetic sensor unit provided to detect a magnetic field arranged near or in the vicinity of the peripheral device unit, and when a magnetic field having a certain strength or more is detected by the magnetic sensor unit, a warning indicating that is displayed. A magnetic resonance imaging apparatus comprising: a display unit. 3. The magnetic resonance imaging apparatus according to claim 1, further comprising movement control means for controlling movement of the magnetic resonance imaging apparatus according to a detection result of the magnetic sensor means. 4. A bed on which a subject is mounted, a magnetic resonance imaging apparatus for moving a radiography chamber to capture a tomographic image of the subject on the bed, and a plurality of magnetic sensor means provided in the radiography chamber. A magnetic resonance imaging apparatus comprising: a display unit configured to display a magnetic sensor unit that has detected a magnetic field having a certain strength or higher among the plurality of magnetic sensor units. 5. The magnetic resonance imaging apparatus according to claim 4, wherein at least one of the magnetic sensor means is arranged on a ceiling or a floor surface of an imaging room. 6. The magnetic resonance imaging apparatus according to claim 4 or 5, wherein at least one of the magnetic sensor means is installed in the vicinity of the surgical field such as the bed or the surgical site fixing tool. 7. The magnetic resonance imaging apparatus according to claim 4, wherein at least one of the magnetic sensor means is worn by an operator or an operator in an imaging room. 8. The magnetic resonance imaging apparatus according to claim 1, wherein the display unit is a monitor unit that can be mounted on a head of an operator or an operator. 9. The magnetic resonance imaging apparatus according to claim 1, wherein the display unit is a monitor unit installed in an imaging room. 10. The magnetic resonance imaging apparatus according to claim 1, wherein the display unit is composed of a sounding unit installed in an imaging room. 11. The magnetic resonance imaging apparatus according to claim 1, wherein the display unit is a warning indicator light provided adjacent to the magnetic sensor unit. 12. The magnetic resonance imaging apparatus according to any one of claims 4 to 11, wherein the magnetic resonance imaging apparatus is configured to be movable, and the movement controls the movement of the magnetic resonance imaging apparatus according to a detection result of the magnetic sensor means. A magnetic resonance imaging apparatus comprising a control means. 13. A bed on which a subject is mounted, and a magnetic resonance imaging apparatus which moves in an imaging room to capture a tomographic image of the subject on the bed, in the vicinity of or near the magnetic resonance imaging apparatus. An object detection unit that detects a distance to an object that is placed and relatively approaches, and a display unit that displays a warning indicating that when an object existing within a certain value is detected by the object detection unit. A magnetic resonance imaging apparatus comprising: 14. A bed on which a subject is mounted, a magnetic resonance imaging apparatus that moves in an imaging room to capture a tomographic image of the subject on the bed, and a bed near or near the magnetic resonance imaging apparatus. A magnetic sensor unit that detects a magnetic field that changes depending on an object that is placed and relatively approaching, and a movement that controls the movement of the magnetic resonance imaging apparatus when the magnetic sensor unit detects a change in the magnetic field of a predetermined value or more. A magnetic resonance imaging apparatus comprising: a control unit. 15. A bed on which a subject is mounted, a magnetic resonance imaging apparatus that moves in an imaging room to capture a tomographic image of the subject on the bed, and peripheral device means that is movable around the bed. A magnetic sensor means for detecting a magnetic field disposed near or in the vicinity of the peripheral device means, and a movement of the magnetic resonance imaging apparatus when a magnetic field having a certain strength or more is detected by the magnetic sensor means. A magnetic resonance imaging apparatus comprising: a movement control unit for controlling. 16. A bed on which a subject is mounted, a magnetic resonance imaging apparatus that moves in an imaging room to capture a tomographic image of the subject on the bed, and a bed near or near the magnetic resonance imaging apparatus. An object detection unit that detects a distance between an object that is arranged and relatively approaches, and movement control that controls the movement of the magnetic resonance imaging apparatus when the object detection unit detects an object existing within a certain value. A safety system for a radiographing room provided with a magnetic resonance imaging apparatus. 17. A sensor means for detecting information that changes depending on a relatively approaching object, and a display means for displaying a warning when a predetermined condition is satisfied based on the information detected by the sensor means. In addition, the sensor means is close to or near either or both of a magnetic resonance imaging apparatus for taking a tomographic image of a subject mounted on a bed and movable peripheral equipment means provided around the bed. A safety system for a magnetic resonance imaging apparatus, characterized in that 18. The magnetic device according to claim 17, wherein the magnetic resonance imaging apparatus includes moving means, and movement control means for controlling the moving means based on information detected by the sensor means. Safety system for resonance imaging equipment.