JP2001321349A - Positioning method of subject for biomagnetism measurement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positioning method of a subject for a measuring. SOLUTION: In a biomagnetism measuring having a SQUID flux meter arranged in x and y directions and a low temperature vessel 36, a first laser 43 irradiates an xz mark, a second laser 40 irradiates a yz mark, and a spot-like laser beam 47 irradiates the intersection of the crossing line of the first and second lasers with the surface of a bed 31. The second laser irradiates so as to pass first and second markers 37 and 28 arranged in a xiphoid process or jugular notch, the bed is moved so that the second laser irradiates the yz mark, and the bed is moved so that the first laser passes a first reference point, so that the line connecting the first and second markers is conformed to or parallel to one direction where the center of the SQUID flux meter is arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a SQUID which is a superconducting device for detecting a weak magnetic field generated from a living body.
(Superconducting Quantum
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biomagnetic field measuring apparatus using a superconducting quantum interference device) magnetometer, and more particularly, to a biomagnetic field measuring apparatus and a biomagnetic field measuring method capable of easily synthesizing functional information on heart activity and a morphological image of the heart. The present invention relates to a data processing method for a magnetic field measurement device and a method for positioning an inspection target.

[0002]

2. Description of the Related Art As shown in FIG. 16, in a conventional biomagnetic measurement apparatus for measuring brain function, a plurality of detection coils 12 are used.
Is arranged on the bottom 11 of the dewar whose outer shape is adjusted to the curvature of the head, and the magnetic field generated by energizing the magnetic field generating coils 13 installed at a plurality of locations on the head is measured by the detecting coil 12, and the magnetic field generating coil is measured. Simulate the relationship between the magnetic field generated by 13 and the output of the detection coil 12. Measurement data from the detection coil 12 and the simulated detection coil 1
By estimating the position of the magnetic field generating coil 13 that minimizes the difference from the output of the magnetic field generator 2, the position coordinates of the position of the head where the magnetic field generating coil 13 is arranged are specified (for example, Japanese Patent Application Laid-Open No. 4-303416). Gazette).

As shown in FIG. 17, in the measurement of a morphological image of a head by an MRI (nuclear magnetic resonance) apparatus, an MRI marker is provided at the same position as the head where the magnetic field generating coil 13 shown in FIG. 21 and MRI marker 2
1 and the tomographic image of the head including the entire head
The position coordinates of the I marker 21 are specified using an MRI image (for example, Japanese Patent Laid-Open No. Hei 4-303416).

[0004] M of the head representing the measurement results and morphology of the brain magnetic field
In the synthesis with the RI image, the relationship between the position coordinates of the magnetic field generating coil 13 and the position coordinates of the MRI marker 21 is obtained, and for example, the position of the active region of the brain obtained by measuring the brain magnetic field is displayed on the morphological image. In this case, the tomographic image of the head is reconstructed using the tomographic image of the head by the MRI apparatus so as to include the coordinates corresponding to the position of the active part, and the active part of the brain and M
RI images are combined and displayed (for example, A. Uc
hida et al. , AVSTM based B
rain Activity Analysis Sy
stem with a Real Head Sha
pe, Recent Advancesin Biom
Agnetism, Edited by T.A. Yoshi
imoto et al. , Tohoku Unive
rity Press, pp177-180, 199
9).

[0005] In the prior art, various methods for setting the positional relationship between a test object mounted on a bed and a dual in a biomagnetic field measuring device have been reported (for example, Japanese Patent Application Laid-Open No. 3-244433, Japanese Patent Application Laid-Open No. 3-244433). JP-A-2-180244, JP-A-4-109929).

[0006]

In the case where the above-mentioned prior art in the measurement of the brain magnetic field is simply applied to the measurement of the biomagnetic field emitted from the chest, the above-mentioned prior art uses the head in the measurement of the brain magnetic field. Is a problem that requires complicated simulation calculation to specify the position coordinates of the magnetic field generating coil arranged to specify the position coordinates of the MRI.
There is a problem that it is necessary to read the coordinates of the I marker.
Furthermore, in synthesizing the measurement results of the brain magnetic field and the MRI image, the relationship between the coordinates of the magnetic field generating coil and the coordinates of the MRI marker is obtained, and the coordinates corresponding to the position of the active region of the brain are obtained using the tomographic image by the MRI apparatus. There is a problem that requires a calculation for reconstructing a tomographic image of the head to include.

An object of the present invention is to provide a biomagnetic field measuring apparatus which solves the above-mentioned conventional problems, and an object of the present invention is to provide a biomagnetic field measuring apparatus for detecting a magnetic field generated from the heart. Position of the sensor array and the position of S
QUID (Superconducting Quant
SUMMARY OF THE INVENTION It is an object of the present invention to provide a biomagnetic field measuring apparatus and a biomagnetic field measuring method that can easily and easily realize an operation of obtaining a large signal output from a tun interference device (superconducting quantum interference device) magnetometer.

It is another object of the present invention to easily create a composite image of functional information relating to the activity of the heart obtained by a biomagnetic field measuring device and a morphological image obtained by an imaging device other than the biomagnetic field measuring device. An object of the present invention is to provide a biomagnetic field measurement device capable of displaying an image.

A further object of the present invention is to provide a data processing method for displaying a composite image in a biomagnetic field measuring apparatus, and a preferred method of positioning an inspection object for a biomagnetic field measuring apparatus when displaying a composite image. Is to provide.

[0010]

A typical configuration of a biomagnetic field measuring apparatus according to the present invention will be described. The biomagnetic field measuring apparatus according to the present invention comprises a bed on which a test object is mounted, a holding table for holding the bed, a low-temperature container for cooling a plurality of SQUID magnetometers, and a low-temperature container which is held at a known distance from the floor. And a gantry fixed to the floor surface. The bottom of the cryocontainer and the top of the bed are arranged substantially parallel to the floor.

[0011] The cryogenic vessel has an xz marker representing an xz plane of a coordinate system (x, y, z) on the outer peripheral surface at the bottom thereof, and yz.
It has a yz marker representing a plane, and in the coordinate system (x, y, z), the xy plane is parallel to the bottom of the cryocontainer and the z-axis is perpendicular to the bottom of the cryocontainer.

A plurality of SQUID magnetometers are arranged in the x-direction and the y-direction, respectively, near the bottom surface inside the cryogenic vessel, and for example, detect a Z-direction component of a magnetic field generated from the heart to be examined. It is. As the plurality of SQUID magnetometers, a magnetometer that detects a component in the x direction and a component in the y direction of the magnetic field generated from the heart to be examined may be used.

As an optical system used for adjusting the positional relationship between the bottom surface of the cryogenic container and the bed, a first laser source for generating a first fan-shaped laser which spreads in a fan shape in the xz plane, and a fan-shaped laser beam in the yz plane. A second laser source for generating a second fan-shaped laser which spreads, and a third laser for generating a point-shaped laser beam which is applied to the bed surface from an oblique direction, intersecting the first and second fan-shaped lasers. Laser source. The first laser source is fixed to a frame fixed to a gantry, the second laser source is fixed to a frame fixed to a holding table, and the third laser source is fixed to a floor, a ceiling, or a wall surface. Frame fixed.

As means for changing the irradiation direction of the lasers generated from the three laser sources, a first position change for changing the irradiation direction of the first fan-shaped laser so that the first fan-shaped laser irradiates the xz mark. Means and the second fan-shaped laser are yz
Second position changing means for changing the irradiation direction of the second fan-shaped laser so as to irradiate the sign; and a point-shaped laser beam, a line at which the first fan-shaped laser intersects with the second fan-shaped laser; , A third position changing means for changing the irradiation direction of the point-like laser beam so as to irradiate the intersection point between the z-axis and the surface of the bed.

As means for moving the bed with respect to the bottom surface of the cryogenic vessel, an x-direction moving means for moving the holding table in the x direction on the floor surface, and a y-direction for moving the bed on the holding table in the y direction. A moving means and a z-direction moving means for moving the bed in the z-direction on the holding table are used.

With the movement of the bed relative to the bottom of the cryogenic vessel, the distance between the bed and the floor is automatically measured by the distance measuring means, and the measured value is displayed on the display.

In this configuration, the first laser from the first laser source
The irradiation direction of the spot-shaped laser beam from the second fan-shaped laser beam, the second fan-shaped laser beam from the second laser source, and the third laser source is changed, and the bed is moved in the x, y, and z directions. With a simple configuration, the height position of the bed can be measured, and the positional relationship between the inspection target mounted on the bed and the bottom surface of the low-temperature container can be adjusted.

In another typical configuration of the biomagnetic field measuring apparatus of the present invention, a plurality of SQUID magnetometers for detecting a magnetic field component in a normal direction of a magnetic field generated from a heart to be examined are provided in a cryogenic container (Dur). It is arranged two-dimensionally at the bottom inside and is cooled to a low temperature. The SQUID magnetometer is driven by a drive circuit drive, and the signal of the magnetic field component of the magnetic field component in the normal direction detected by the SQUID magnetometer is collected by an arithmetic processing unit such as a computer that performs arithmetic processing and controls each unit of the apparatus. You. Prior to the measurement, a first marker indicating a first reference point on the body surface at a first point on the chest to be inspected and a second marker on the body surface at a second point on the chest to be inspected. The indicated second markers are respectively arranged.

The coordinate system (x, y,
z) is set, and the fan-shaped laser spreads in a fan shape in the xz plane.
Using a total of three lasers, a fan-shaped laser that spreads in a fan shape parallel to the yz plane and a point-like laser beam that crosses the two fan-shaped lasers and irradiates the bed surface from an oblique direction The positional relationship between the upper chest surface to be inspected and the bottom surface of the Dua is adjusted. Coordinate system (x, y, z)
Xy plane is set as the measurement plane by the SQUID magnetometer. The bottom surface of the dewar is parallel to the xy plane, the measurement surface, and the top surface of the bed, and the distance between the top surface of the bed and the bottom surface of the dewar is known.

[0020] The bed is moved in the z direction to a position sufficiently higher than the height of the body surface of the test object when the test object is mounted with the bed at the lowest height, and three lasers are used.
The irradiation direction of the point-like laser beam is set so that the point of intersection of the z-axis and the bed surface is irradiated with the above-mentioned point-like laser beam. Measure the distance. The inspection object is mounted on the bed by lowering the bed to a low position, and the fan-shaped laser spreading in a fan shape in a plane parallel to the yz plane is parallel to the yz plane so as to pass through the first reference point and the second reference point. X is a fan-shaped laser that spreads in a fan
In the direction, the line connecting the first reference point and the second reference point is parallel to one direction in which the center of the SQUID magnetometer is arranged, or 1 is the line in which the center of the SQUID magnetometer is arranged.
Adjust the position of the inspection target so that it matches the direction.

Next, the fan-shaped laser spreading in a fan shape in the xz plane moves the bed in the y-direction so as to pass through the first reference point, and the fan-shaped laser spreading in a fan parallel in the plane parallel to the yz plane becomes y.
After moving the bed in the x direction so as to coincide with the z plane, the bed is moved in the z direction until the irradiation point of the point-like laser beam coincides with the first reference point. next,
The bed is moved in the z-direction until the body surface to be inspected touches the bottom surface of the dewar, the amount of movement is determined, and the chest to be inspected is placed in contact with the bottom surface of the dewar. Can be determined. Since the positions of the xiphoid process and the cervical notch can be easily determined with good reproducibility by palpation, the first point is the body surface position of the xiphoid to be inspected, and the second point is the position of the cervical notch to be inspected. It is preferable to select the body surface position.

The arithmetic processing unit comprises: (1) a process for creating an image representing functional information relating to the activity of the heart to be inspected from the signal of the magnetic field waveform; and (2) a process for forming an image on the body surface at a first point on the chest to be inspected. A first marker indicating one reference point is arranged,
Processing for creating a functional image having pixels of the same size as the morphological image by matching the pixel size of the image representing the function information with the pixel size of the morphological image of the chest to be inspected taken by the imaging device (3) processing for matching the position of the first reference point in the functional image with the position of the first marker in the morphological image; (4) creating a composite image of the functional image and the morphological image And a data processing method including the following.
Prior to the processing of (4), (3 ′) the morphological image is rotated about the first reference point, and the body axis direction of the inspection target in the morphological image and the inspection target in the functional image are rotated. Is performed to match the pixel arrangement direction in the body axis direction.

Further, the arithmetic processing unit performs the process (1) by executing the following data processing method. (A) A process of estimating an activated part of a heart to be examined as a current source using a signal of a measured magnetic field waveform of a magnetic field component in a normal direction, and determining a position of the current source as an image representing functional information. And processing for creating an image including the image. Performs processing to determine the tangential magnetic field component of the magnetic field generated from the heart to be examined from the measured normal magnetic field component, and performs the following processing using the magnetic field waveform signal of the tangential magnetic field component .
(B) A process of creating an isomagnetic field map connecting coordinate points having the same magnetic field strength is performed to obtain an isomagnetic field map as an image representing function information. (C) A process of creating an arrow map that displays the activated site of the heart to be examined as a two-dimensional current distribution is performed, and an arrow map is obtained as an image representing functional information. (D) integrating the magnetic field waveform in a time interval including a specific phase of the activity of the heart to be examined to obtain an integrated intensity;
A process of creating an isomagnetic field integral diagram connecting coordinate points having the same integral intensity is performed, and an isomagnetic field integral diagram is obtained as an image representing function information. (E) 2 different activities of the heart to be examined
Integrate the magnetic field waveforms of the tangential magnetic field components in the time section including two phases to obtain the integrated strength, and connect the coordinate points with the same value of the difference between the integrated strengths in the time section including two different phases. A process for creating an isomagnetic field integral diagram is performed to obtain an isomagnetic field integral diagram as an image representing function information.

The morphological image is, for example, a tomographic image substantially parallel or perpendicular to the plane of the chest of the examination object taken by the MRI apparatus, or a substantially parallel or vertical plane to the plane of the chest of the examination object taken by the three-dimensional XCT apparatus. It is selected from any of a tomographic image and a chest X-ray image of the examination target captured by the X-ray imaging apparatus. Using the selected morphological image and any of the images representing the function information obtained by (a) to (e),
The arithmetic processing unit executes a data processing method including the processes (2) to (4) and (3 ′).

According to the configuration of the present invention described above, prior to detection of the magnetic field generated from the heart to be examined, a simple configuration using a total of three lasers, two fan-shaped lasers and a point-shaped laser beam, is used. The positional relationship between the surface of the chest to be inspected on the bed and the bottom surface of the Dua can be adjusted. As a result, almost the entire projection of the heart onto the surface of the sensor array is located within the area of the sensor array, and the body surface of the chest to be inspected comes into contact with the lower surface of the dual, so that a large signal output is obtained. The above operation of adjusting the positional relationship can be executed easily in a short time.

Also, according to the present invention, a complex calculation such as a simulation calculation of a magnetic field generation for estimating a magnetic field source and a calculation for reconstructing a tomographic image is not performed, and a biological magnetic field obtained by a biomagnetic field measuring apparatus can be obtained. Function information, especially function information on the activity of the heart expressed by isomagnetic field maps, arrow maps, isomagnetic field integral maps, and results of current dipole position estimation obtained from the magnetic field waveform obtained by measuring the magnetic field emitted from the heart , Nuclear magnetic resonance (MRI) equipment, three-dimensional XC
A composite image with a morphological image (tomographic image) substantially parallel or perpendicular to the plane of the chest obtained by a T device or the like, or a composite image with a transmission image such as a chest X-ray image obtained by an X-ray imaging apparatus can be easily obtained. And a composite image can be displayed.

In many cases, in the MRI apparatus and the three-dimensional XCT apparatus, the bed on which the object to be inspected is mounted is held horizontally, and in imaging, the object to be inspected is the longitudinal axis of the bed and the body axis of the object to be inspected. It is mounted on the bed so that it almost matches. In addition, chest X-ray images (X-ray transmission images) obtained by an X-ray imaging apparatus are often taken in an upright position or in a normal sitting position in a chair, and are taken while lying on a bed in a general ward. It may be done.

Even when the longitudinal direction of the bed and the body axis of the object to be inspected do not exactly coincide with each other in imaging with an MRI apparatus or a three-dimensional XCT apparatus, the morphological image can be obtained by performing the processing of (3 '). The alignment direction of the pixels in the body axis direction of the test object in the functional image and the body axis direction of the test object in the functional image (the direction connecting the first reference point and the second reference point) may be matched. it can.

That is, a composite image of the image obtained by rotating the morphological image around the first reference point (the position of the center of the image of the MRI marker or the position of the center of the image of the X-ray marker) is created. Therefore, a more accurate composite image of the functional image and the morphological image can be created. For example, the morphological image is set to the first line so that the center line of the spine in the chest X-ray image (X-ray transmission image) and the arrangement direction of the pixels in the body axis direction of the inspection target in the functional image match. By rotating around the reference point (the position of the center of the image of the X-ray marker), a more accurate composite image of the functional image and the morphological image can be created.

A typical configuration of a biomagnetic field measuring apparatus for obtaining a composite image of an image representing biological function information and a morphological image in the present invention is summarized as follows with reference to FIG. A first marker 37 indicating a first reference point is arranged on the body surface of the xiphoid process of the inspection target 35, and a second marker 38 indicating a second reference point is arranged on the body surface of the cervical notch. 1,
The line connecting the second reference points is the SQUA inside the cryocontainer 36.
The chest is arranged at the lower part of the bottom surface of the cryogenic vessel so as to be along one direction in which the ID magnetometers are arranged. The processing unit is
(1) a process of creating an image representing functional information related to the activity of the heart from a signal of a magnetic field waveform; and (2) a first marker indicating a first reference point is arranged on the body surface of the xiphoid process, and (3) processing for matching the size of the pixel of the image representing the function information with the size of the pixel of the morphological image including the heart captured by the above to create a functional image having pixels of the same size as the morphological image, Executes processing to match the position of the first reference point in the functional image with the position of the first reference point in the morphological image, and (4) processing to create a composite image of the functional image and the morphological image I do.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A biomagnetic field measuring apparatus according to the present invention includes a bed, a holding table for holding the bed, a low-temperature container, and a gantry. On the surface near the bottom inside the cryogenic vessel,
A plurality of SQUID magnetometers are arranged in the x direction and the y direction, respectively, and are cooled. An xz mark indicating the xz plane and a yz mark indicating the yz plane of the coordinate system (x, y, z) are marked on the outer peripheral surface at the bottom of the cryogenic container. In the coordinate system (x, y, z), the xy plane is parallel to the bottom of the cryocontainer, and the z-axis is perpendicular to the bottom of the cryocontainer.

The gantry holding the cryogenic vessel is fixed to the floor. The distance between the bottom surface of the cryogenic container and the floor surface is a known value set in advance, and the bottom surface of the cryogenic container is at a position fixed with respect to the floor surface. The bottom of the cryocontainer and the top of the bed are arranged substantially parallel to the floor.

As the plurality of SQUID magnetometers, a magnetometer for detecting a magnetic field component in the Z direction or a magnetometer for detecting a magnetic field component in the x direction and a magnetic field component in the y direction are used.

As an optical system used for adjusting the positional relationship between the bottom surface of the low-temperature container and the bed, a first laser source for generating a first fan-shaped laser spreading in a fan shape in the xz plane, and a fan-shaped laser beam in the yz plane are used. A second laser source for generating a spreading second fan-shaped laser, and a third laser for generating a point-shaped laser beam for irradiating the bed surface from an oblique direction so as to intersect the first and second fan-shaped lasers. Laser source. The first laser source is fixed to a frame fixed to the gantry,
The second laser source is fixed to a frame fixed to the holding table, and the third laser source is fixed to a frame fixed to any of the floor, ceiling, and wall.

As means for changing the irradiation direction of the lasers generated from the three laser sources, a first position change for changing the irradiation direction of the first fan-shaped laser so that the first fan-shaped laser irradiates the xz mark. Means and the second fan-shaped laser are yz
Second position changing means for changing the irradiation direction of the second fan-shaped laser so as to irradiate the sign; and a point-shaped laser beam, a line at which the first fan-shaped laser intersects with the second fan-shaped laser; , A third position changing means for changing the irradiation direction of the point-like laser beam so as to irradiate the intersection point between the z-axis and the surface of the bed.

As means for moving the bed relative to the bottom surface of the cryogenic vessel, an x-direction moving means for moving the holding table in the x direction on the floor surface, and a y-direction for moving the bed on the holding table in the y direction. A moving means and a z-direction moving means for moving the bed in the z-direction on the holding table are used.

As the position of the bed moves relative to the bottom of the cryogenic vessel, the distance between the bed and the floor is automatically measured by the distance measuring means, and the distance is displayed on the display.

A typical positioning method and a biomagnetic field measuring method described below are applied to the above-described biomagnetic field measuring apparatus.

A typical method of positioning an inspection object for a biomagnetic field measuring apparatus according to the present invention is as follows. (1) The irradiation direction of the first fan-shaped laser is adjusted so that the first fan-shaped laser irradiates the xz mark. (2) The irradiation direction of the second fan-shaped laser is set so that the second fan-shaped laser irradiates the yz mark. (3) The point-shaped laser beam is emitted from the first fan-shaped laser and the second fan-shaped laser. The irradiation direction of the point-like laser beam is set so as to irradiate the line where the fan-shaped laser crosses and the crossing point between the z-axis and the bed surface. (4) The second fan-shaped laser in the yz plane Is a first reference point indicated by a first marker located on the body surface at a first point on the chest to be examined, and a second reference point located on the body surface at a second point on the chest to be examined. The irradiation direction of the second fan-shaped laser is set so as to pass through the second reference point indicated by the marker. And, (5) a second fan-shaped laser y
Move the bed in the x direction to illuminate the z sign,
(6) By moving the bed in the y direction so that the first fan-shaped laser passes through the first reference point in the yz plane, a line connecting the first reference point and the second reference point becomes The chest to be inspected is placed below the bottom of the cryocontainer so that the center of the SQUID magnetometer matches or is parallel to one direction in which it is arranged.

The above positioning method further comprises: (7) moving the bed in the z direction until the irradiation point of the point-like laser beam coincides with the first reference point; Moving the bed in the z-direction until it comes into contact with the bottom of the cryogenic vessel, and determining the distance between the first reference point and the bottom of the cryogenic vessel. The first point is the xiphoid to be inspected,
As a second point, the cervical notch to be examined is used.

The representative biomagnetic field measuring method for a biomagnetic field measuring apparatus according to the present invention is as follows: (1) The first fan-shaped laser fan-shaped in the xz plane irradiates the xz marker with the first fan-shaped laser.
(2) The irradiation direction of the second fan-shaped laser is set so that the second fan-shaped laser spreading in a fan-like manner in the yz plane irradiates the yz mark, and (3) the irradiation direction of the second fan-shaped laser is set. 1
A point-like laser beam applied to the surface of the bed from an oblique direction so as to intersect the fan-shaped laser and the second fan-shaped laser is a line where the first fan-shaped laser intersects with the second fan-shaped laser, and , The irradiation direction of the point-like laser beam is set so as to irradiate the intersection between the z-axis and the surface of the bed,
(4) In the yz plane, the second fan-shaped laser emits a first reference point indicated by a first marker disposed on the body surface of the xiphoid projection to be inspected, and the body surface of the cervical notch to be inspected (5) The irradiation direction of the second fan-shaped laser is set so as to pass through the second reference point indicated by the second marker arranged in the bed, and (5) the bed is set so that the second fan-shaped laser irradiates the yz mark. X
(6) The bed is moved in the y-direction so that the first fan-shaped laser passes through the first reference point in the yz plane, and (7) the irradiation point of the point-like laser beam is the first point. (8) The bed is moved in the z direction until the bed coincides with the reference point of (8) until the body surface to be inspected contacts the bottom of the cryogenic container.
Then, the distance between the first reference point and the bottom surface of the cryogenic vessel is determined by moving in the direction, and then (9) the magnetic field generated from the heart to be examined is detected. The chest to be inspected is placed at the bottom of the bottom of the cryogenic vessel so that the line connecting the first and second reference points coincides or is parallel to one direction where the center of the SQUID magnetometer is arranged. Is done.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. (First Embodiment) FIG. 1 is a diagram showing an example of the overall configuration of a biomagnetic field measuring apparatus according to a first embodiment of the present invention, and FIG.
FIG. 2 is a diagram illustrating details of a configuration example of the biomagnetic field measurement apparatus according to the first embodiment of the present invention. As shown in FIG. 1, a bed 3 on which an inspection target 35 lies
1 and a gantry 4 holding a dua (cryogenic container) 36
6 are arranged. A plurality of sensors (SQ) for detecting a magnetic field signal in the z direction (normal direction) generated from the living body
UID magnetometers) are arranged two-dimensionally in a grid pattern in the x and y directions near the bottom inside the dewar 36 (a plurality of sensors arranged two-dimensionally are called a sensor array).

As shown in FIG. 4, 64 SQUID magnetometers for measuring a weak magnetic field generated from the heart are provided at the bottom of the inside of the cryogenic vessel (Dur) 36 at each grid point of an 8 × 8 square grid. Are arranged two-dimensionally. Each SQUID magnetometer has a primary differential detection coil having a detection coil and a compensation coil, and detects a magnetic field in a normal direction (z direction, a direction perpendicular to the body surface).

The sensor array is driven by a drive circuit 6, and the output from the sensor array is amplified by an amplifier filter unit 7, filtered, and then collected by a computer (arithmetic processing unit) 8.

The computer (arithmetic processing unit) 8 performs an operation for obtaining an average magnetic field waveform in the normal direction or an added magnetic field waveform of the magnetic field generated from the heart detected by the sensor array, and then executes the average magnetic field in the normal direction. The magnetic field component in the tangential direction of the magnetic field generated from the heart is determined from the waveform or the added magnetic field waveform. Further, using the tangential magnetic field component, the computer 8
Analyzes the magnetic field distribution at coordinate points where multiple sensors are arranged, creates an isomagnetic field map connecting coordinate points with the same magnetic field strength, and sets the activated part of the heart to be examined as a two-dimensional current distribution. Creation of an arrow map to be displayed, integration of magnetic field waveforms in a time interval including a specific time phase (time zone) of heart activity, calculation of integral strength, creation of isomagnetic field integral maps connecting coordinate points having equal integral strength, Various arithmetic processing such as estimating the position of the current source from the magnetic field component in the normal direction is performed, and the processing result is displayed on the display device.

A method for determining a tangential magnetic field component from a normal magnetic field component is described below.
The method of creating an isomagnetic field diagram and the method of creating an isomagnetic field integral diagram are methods first developed by the present inventors.
This is a known technique (see Japanese Patent Application Laid-Open No. 10-305019).

Let t be a time variable, the coordinates of the SQUID magnetometer be (x, y), and the measured magnetic field component in the normal direction be Bz
When (x, y, t), the tangential magnetic field component Bx
(X, y, t) and By (x, y, t) are obtained by (Equation 1) and (Equation 2).

[0048]

Bx (x, y, t) = ∂Bz (x, y, t) / ∂x (Formula 1)

[0049]

## EQU2 ## By (x, y, t) = ， Bz (x, y, t) / ∂y (Equation 2) As shown in FIG. 2, the biomagnetic field measuring apparatus according to the first embodiment performs an inspection. A y-axis direction moving means for moving the bed 31 on which the object 35 is mounted in the left-right direction (y-axis direction) 32; an x-axis direction moving means for moving the bed 31 in the front-rear direction (x-axis direction) 33; (In the axial direction) 34. The upper surface of bed 31 is Dua 3
6 is always held parallel to the bottom surface, that is, parallel to the xy plane. The bed 31 is held by a bed holding table 31-1, and can be moved on the feed rail 31-2 in the x-axis direction 33 by operating a front-rear feed handle (not shown).
Numeral 1 is movable on the bed holding base 31-1 in the y-axis direction 32 by operating a left / right feed handle 31-3, and the bed 31 is moved on the bed holding base 31-1 by a hydraulic pump handle 31-4. To move in the z-axis direction.

In the biomagnetic field measuring apparatus according to the present invention, the spatial position of the dewar 36 is fixed, and the measurement surface (401 shown in FIG. 5) is set as the xy surface, for example, a sensor (SQUID magnetometer) having a detection coil. A coordinate system (x, y, z) of the biomagnetic field measuring apparatus is set with the origin (0, 0, 0) at the center of gravity of each coordinate point (x, y) of (402 shown in FIG. 5). As the origin of the coordinate system (x, y, z), the position of the sensor arranged at a specific position in the sensor array is defined as the origin (0,
(0,0). The sensor is located on the measurement surface parallel to the bed 31 near the bottom inside the dewar 36 (4 in FIG. 5).
01), they are two-dimensionally arranged in a grid in the x and y directions.

An xz marker 36-1 indicating the intersection of the xz plane of the coordinate system (x, y, z) and the outer peripheral side, and a yz plane and the outer peripheral side are provided on the outer peripheral side of the lower part of the dure 36. A yz marker 36-2 indicating the intersection line of is indicated.

The biomagnetic field measuring apparatus according to the first embodiment arranges the inspection object 35 on the bed 31 in a fixed direction and at a fixed position with respect to the bottom surface of the dual 36 so that the length of the bed 31 is long. A laser oscillator 41 for emitting a fan-shaped laser 40 extending in the axial direction 39, a laser oscillator 44 for emitting a fan-shaped laser 43 extending in the short-axis direction 42 of the bed 31, and a coordinate system (x, y, z) by changing the irradiation direction. ), A laser oscillator 48 for emitting a point-like laser 47 crossing the z-axis, an ultrasonic displacement sensor 45 for measuring the displacement of the bed 31 from the floor surface, and the like. The spread angles of the laser 40 radiated in a fan shape on a plane parallel to the yz plane and the laser 43 radiated in a fan shape on a plane parallel to the xz plane can be changed. An intersection line 49 between the fan-shaped laser 40 and the fan-shaped laser 43 is parallel to the z-axis of the coordinate system (x, y, z). The wavelength of the laser 40, the laser 43, and the laser 48 is 300 nm to 850 nm, and the wavelength range is 300 nm to 8 instead of the laser 40, the laser 43, and the laser 48.
Other light sources that emit 50 nm light may be used.

The laser oscillator 41 has an oscillator holder 41-1.
And the oscillator holder 41-1 is attached to the bed holder 31.
The laser 4 is attached to the pipe frame 41-2 fixed to -1.
The irradiation direction of 0 can be changed and the irradiation direction can be fixed so as to be a specific direction (second position changing means).
Similarly, the laser oscillator 44 is held by an oscillator holder 44-1. The oscillator holder 44-1 is mounted on a pipe frame 44-2 fixed to a gantry 46 so that the irradiation direction of the laser 43 can be changed and the irradiation direction can be changed. Can be fixed so as to be in a specific direction. That is, the oscillator holder 41-1 is
It can move in the x-axis direction 33 on the pipe frame 41-2, and can rotate (tilt) around the axis of the pipe frame 41-2 (first position changing means).

Similarly, the oscillator holder 44-1 is movable in the y-axis direction 32 on the pipe frame 44-2, and is rotatable (tilted) around the axis of the pipe frame 41-2. The pipe frame 41-2 is a bed 3
1 bed holding base 31-1 on the side of the human foot mounted on
To prevent light in the wavelength range of 300 nm to 850 nm from entering the eyes. Pipe frame 44-2
Project in the horizontal direction above the position of the dewar 36.

The laser oscillator 48 includes an oscillator holder 48-
1, the oscillator holder 48-1 is fixed to a floor, ceiling, or wall surface of a pipe frame 48-2 so that the irradiation direction of the point laser 47 can be changed and the irradiation direction is specified. The direction can be fixed. The oscillator holder 48-1 can move on the pipe frame 48-2 in the y-axis direction 32, and can rotate (tilt) around the axis of the pipe frame 48-2. Pipe frame 48
-2 is fixed to the floor or wall inside the magnetically shielded room.

In order to measure the magnetic field generated from the heart of the test object 35, the test object 35 is placed in a fixed direction and a fixed direction with respect to the bottom surface of the dual 36, that is, in the coordinate system (x, y, z). Positioning operation, for example, in order to position almost the entire projection of the heart on the surface of the sensor array within the area of the sensor array, so that the body surface of the chest of the test object 35 is in contact with the lower surface of the dewar 36 The operation of
This will be described with reference to FIG.

FIG. 3 shows a first embodiment of the present invention.
FIG. 4 is a schematic view showing an example of a procedure for arranging an inspection target mounted on a bed on the lower surface of a dure, and FIG. 4 is a diagram illustrating an inspection target mounted on a bed on a lower surface of the dure in the first embodiment of the present invention. It is a figure explaining adjustment of irradiation direction of three lasers used at the time of arrangement.

In the first embodiment described below, the z-axis of the coordinate system (x, y, z) is used so that almost the entire projection of the heart onto the xy plane is located within the area of the sensor array. Pass through the preset sensor position. That is,
The position of the test object is adjusted with respect to the sensor array so that the xiphoid to be examined passes through the z-axis so that almost the entire projection of the heart onto the surface of the sensor array is located within the area of the sensor array. I do.

Step 1 (reference numeral 51): First, bed 3
1 is moved in the x direction and / or the y direction so that the bed 31
Is moved below the dewar 36. Next, the bed 31 is moved in the z-axis direction 34 so that the height of the upper surface of the bed 31 is higher than the height of the body surface of the inspection target when the inspection target 35 is mounted with the bed 31 being the lowest height. Set so that At this time, the height HL of the bed 31 from the floor surface is measured by the ultrasonic displacement sensor 45. The height of the bed 31 from the floor surface can be measured by a general displacement sensor (distance measuring means). For example, an optical displacement sensor that detects displacement optically is used instead of the ultrasonic displacement sensor 45. You can also. Note that the height of the bed 31 from the floor surface is determined by the distance between the upper surface of the bed 31 and the floor surface or an arbitrary position of the bed 31 at a position in the z-axis direction 34 at a fixed distance from the upper surface of the bed 31. Attached to
This is the distance between the position of the displacement sensor that moves with the upper surface of the bed 31 by the z-axis direction moving means in the z-axis direction 34 and the floor surface.

By moving the position of the oscillator holder 44-1 on the pipe frame 44-2, the laser 43 (oscillated from the laser oscillator (first laser light source)) 44 and spreading in a fan-like manner on a plane parallel to the xz plane is shown. By changing the angle of spread of the fan 1 laser as needed, the laser 43
At the position where the upper surface of the bed 31 is irradiated through the xz mark 36-1 written on the side surface of the lower periphery of the lower part of the oscillator 6, the oscillator holder 4
The position 4-1 is fixed to the pipe frame 44-2.

The position of the oscillator holder 41-1 is moved above the pipe frame 41-2, and the laser 40 (the second laser light source) oscillated from the laser oscillator (second laser light source) 41 and spreads in a fan-like shape on a plane parallel to the yz plane. The angle of the spread of the fan 2 laser is changed as necessary, and the laser 40
At the position where the upper surface of the bed 31 is illuminated through the yz mark 36-2 written on the side surface of the outer periphery of the lower part of the oscillator 6, the oscillator holder 4
The position 1-1 is fixed to the pipe frame 41-2.
The fan-shaped laser 40 and the fan-shaped laser 43 intersect to form an intersecting line 49 parallel to the z-axis of the coordinate system (x, y, z).

FIG. 4 is a flow chart showing steps 3 in step 2 described below.
FIG. 4 is a diagram for explaining adjustment of a laser irradiation direction.

Step 2 (reference numeral 52): oscillator holder 4
The laser oscillator is moved by the movement in the y-axis direction 32 on the pipe frame 48-2 at the position 8-1 and the rotation (tilt) about the axis of the pipe frame 48-2 at the position of the oscillator holder 48-1. (Third laser light source) Point-like laser (laser beam) oscillated from 48 (third laser) 4
7, the irradiation direction of the laser 7 is changed, and the laser 47 is moved to the coordinate system (x,
The position of the oscillator holder 48-1 is fixed to the pipe frame 48-2 so as to intersect the intersection line 49 parallel to the z-axis of (y, z) with the surface of the bed 31. That is, first, the oscillator holder 48- is set so that the laser 47 irradiates the xz marker 36-1.
After the position 1 is set, the oscillator holder 48-1 is rotated (tilted) around the axis of the pipe frame 48-2 so that the laser 47 and the intersection line 49 intersect at the surface of the bed 31. The position of 48-1 is fixed (third position changing means).

Step 3 (reference number 53): The ultrasonic displacement sensor 45 causes the laser 47 and
The vertical distance H0 between the point of intersection at the surface and the lower surface of the dual 36 is determined. The bed 31 is moved in the z-axis direction so that the surface of the bed 31 contacts the lower surface of the dewar 36, and the height HH of the bed from the floor is measured by the ultrasonic displacement sensor 45. H0 = (HH-HL).

Step 4 (reference numeral 54): The bed 31 is sufficiently far away from the projection position of the bottom of the dewar 36 onto the floor, and the bed 31 is moved to a position where the dewar 36 does not become an obstacle when the inspection object 35 is mounted on the bed 31. Is moved in the x-axis direction 33, the bed 31 is moved in the z-axis direction, and the height of the bed 31 is lowered. The inspection target 35 is mounted on the bed 31 such that the body axis direction of the inspection target 35 is substantially parallel to the long axis direction 39 of the bed 31. Two reference points (first and second reference points) 37 and 38 are provided on the body surface of the chest along the body axis of the inspection target 35.

For example, the position of the xiphoid process (first reference point) is selected as the position of the reference point 37, and the cervical notch (second reference point) is selected as the position of the reference point 38. The locations of the xiphoid process and the cervical notch can be easily determined by palpation.
The body surface position of the cervical notch can be used as a reference point. Reference point 37, 3
8, a marker described later is attached.

Step 5 (reference numeral 55): oscillator holder 4
1-1 is moved on the pipe frame 41-2, and the irradiation direction of the laser 40 oscillated from the laser oscillator 41 and spread in a fan shape on a plane parallel to the yz plane is changed. The movement of the position of the oscillator holder 41-1 on the pipe frame 41-2 and / or the movement of the inspection target 35 on the bed 31 are performed so as to pass through each center.

As a result, a line passing through the centers of the reference points 37 and 38 becomes parallel to the long axis direction 39 of the bed 31, and the fan-shaped laser 40 passes through the centers of the reference points 37 and 38 so that the oscillator holder 41 can move. The position of -1 is fixed to the pipe frame 41-2.

Step 6 (reference numeral 56): laser oscillator 4
The bed 31 is moved in the y-axis direction 32 so that the laser 43 passes through the center of the reference point 37 by changing the spread angle of the fan-shaped laser 43 oscillated from 4 as needed. As a result, the intersection line 49 of the cross beam pattern formed by the lasers 40 and 43 coincides with the center of the reference point 37. In this state, the movement of the bed 31 in the y-axis direction 32 is locked.

Step 7 (reference numeral 57): laser oscillator 4
The angle of the spread of the fan-shaped laser 40 oscillated from 1 is changed as necessary, and the bed 31 is moved so that the laser 40 passes through the yz mark 36-2 marked on the outer peripheral side of the lower part of the dual 36. Is moved in the x-axis direction 33. Laser 4
At a position where 0 passes through the yz marker 36-2, the movement of the bed 31 in the x-axis direction 33 is locked. As a result, a state where the z-axis of the coordinate system (x, y, z) passes through the center of the reference point 37 is realized.

Step 8 (reference numeral 58): The bed 31 is moved in the z-axis direction 3 so that the laser 47 passes through the center of the reference point 37.
4, the height H1 of the bed 31 from the floor is measured by the ultrasonic displacement sensor 45. As a result,
The vertical distance between the reference point 37 and the bottom of the Dewar 36 is always H0 = (HH−
HL).

Step 9 (reference numeral 59): Finally, the bed 31 is moved in the z-axis direction 34 so that the body surface of the chest of the inspection object 35 is brought close to the lower surface of the dual 36, and a large signal output is obtained. To do. Next, the ultrasonic displacement sensor 45
The height H2 of the bed 31 from the floor is measured.
The vertical distance H3 between the reference point 37 and the bottom surface of the dewar 36 when the body surface of the chest of the inspection subject 35 is brought close to the lower surface of the dewar 36 differs depending on the body shape of the inspection subject 35, but H3 =
{H0- (H2-H1)}.

As described above, the reference points 37, 38,
By using three laser light sources, almost the entire projection of the heart onto the surface of the sensor array is located in the area of the sensor array, and the body surface of the chest of the test object 35 contacts the lower surface of the dewar 36, and a large signal An operation for obtaining an output can be easily realized in a short time.

In the imaging of the morphological image by the MRI apparatus, the center of the MRI marker is arranged at the same position of the chest as the center position of the reference point 37, the body axis is aligned with the long axis of the bed 31 of the MRI apparatus, and the surface of the bed is adjusted. And multiple tomographic images of different depths are taken. Of course, these plurality of tomographic images include tomographic images in which MRI markers are captured.

FIG. 5 is an example of a display screen of information obtained by measurement and analysis using the biomagnetic field measuring apparatus according to the first embodiment of the present invention. FIG. In the example shown in FIG. 5, the origin of the coordinate system (x, y, z) is set at the position of the sensor 400 arranged at a specific position among the plurality of sensors 402 arranged on the measurement surface 401 parallel to the bed 31. Then, the reference point 37 is attached to the position 404 of the xiphoid process of the inspection object 35, and the xiphoid process 4 is attached.
This is the result of measuring the magnetic field generated from the heart by arranging the inspection target 35 so that the reference numeral 04 passes through the z-axis of the coordinate system. FIG.
Is the intersection of the sword-shaped projection 404 on the surface 403 at a depth c parallel to the measurement surface 401 and the surface 405 at a depth d parallel to the measurement surface 401 with the z-axis of the coordinate system (open white). X) 4
It is an example of a display screen on the display device of the biomagnetic field measuring apparatus, which indicates that the active site 406 indicated by the white arrow is specified at the tip position of the arrow 406-1 indicated by the solid line from 00-1.

The vertical distance H4 between the measurement surface 401 and the lower surface of the Dewar 36 is known, and the depth c from the measurement surface 401 to the swordlike projection 404 is c = (H3 + H4) = ｛H0−
(H2-H1) + H4}.

As shown in FIG. 4, in the example shown in FIG. 5, the z-axis passes through the position of the xiphoid projection and the z-axis passes through the position of the sensor arranged at a specific position of the sensor array (x ,
y, z) are set. It is well known that the estimation of the position of the current source, that is, the estimation of the active site is possible by various analysis methods for estimating the current source.

The image indicating whether or not the estimated position of the active site exists has a plurality of pixels having coordinates corresponding to the SQUID magnetometers arranged two-dimensionally in a grid in the x and y directions. In the image at the depth (z) where the estimated position of the part exists, the size of the current source is assigned to the pixel at the coordinates (x, y) of the estimated position of the active part, and the active part does not exist The pixel at the coordinates (x, y) estimated to be zero is assigned. Alternatively, as shown in FIG. 5 and an example of FIG. 7 described later, data (direction and size of the current source) indicating a white arrow indicating the direction and size of the current source are added to the estimated position of the active site 406. You may give.

Here, x, y of the image representing the estimated position of the active site on the display screen of the display device of the biomagnetic field measuring device.
The size in the direction is a, b (FIG. 5), the number of pixels in the x, y direction is nx, the size of the pixel in the ny, x, y direction is Δx,
Let it be Δy. a = nxΔx, b = nyΔy. SQ
Assuming that the measurement area in which the UID magnetometer is two-dimensionally arranged in a grid in the x and y directions on the measurement surface is Px and Py, the imaging magnification in the x and y directions of the image obtained by the biomagnetic field measurement device is (a
/ Px) and (b / Py).

FIG. 6 is a display showing a position of a tomographic image (morphological image) by the MRI apparatus which is combined with an image representing the estimated position of the active site obtained by the biomagnetic field measuring apparatus in the first embodiment of the present invention. FIG. 8 is a diagram illustrating an example of a display screen of a plurality of tomographic images including a tomographic image in which an MRI marker is captured, on a display device of the biomagnetic field measuring apparatus.

In the imaging by the MRI apparatus, a tomographic image 407 including the MRI marker 408 arranged at the reference point 37 and parallel to the bed surface and a plurality of tomographic images different in depth (z) parallel to the tomographic image 407 are provided. Shooting is possible.

Here, the size of the image of the tomographic image by the MRI apparatus in the x and y directions is e and f (FIG. 6), and the number of pixels in the x and y directions is the number of pixels in the NX, NY, x and y directions. The size of Δ
X and ΔY. Assuming that the imaging region of the tomographic image by the MRI apparatus is Qx, Qy, the imaging magnification of the tomographic image in the x direction is (e / Qx), and the imaging magnification of the tomographic image in the y direction is (f / Qy). . e = NXΔX, f = NYΔY.

In the first embodiment of the present invention, in order to combine the image representing the estimated position of the active site obtained by the biomagnetic field measuring device and the morphological image by the MRI device, M
The distance (d−d) shown in FIG. 5 is selected from among a plurality of tomographic images captured by the RI device and having different depths parallel to the tomographic image 407.
It is necessary to extract the tomographic image 409 at the depth g corresponding to c). When the thickness of the tomographic image 409 at the depth g is L, the tomographic image 409 can be expressed as 断層 (dc) /
This is the L｝ th fault. In FIG. 6, a white + mark 4
08-1 indicates the position of the xiphoid process in the tomographic image 409.

FIG. 7 shows a composite image of an image representing the estimated position of an active part obtained by the biomagnetic field measuring apparatus and a morphological image (tomographic image) obtained by the MRI apparatus in the first embodiment of the present invention. FIG. 4 is a diagram showing an example of a display screen on a display device of the biomagnetic field measuring apparatus. A procedure for creating a composite image of an image representing the estimated position of the active site and a tomographic image by the MRI apparatus will be described below.

First, in order to combine two images, it is necessary to make the photographing magnification of the image 405 representing the estimated position of the active site and the photographing magnification of the tomographic image 407 the same. That is, 2
The pixels of one image need to be the same size.

A = nxΔx, b = nyΔy, e = NXΔ
Since X and f = NYΔY, in order to make the pixel sizes Δx and Δy of the image 405 equal to the pixel sizes ΔX and ΔY of the tomographic image, Δx is multiplied by (ΔX / Δx) and Δy is (ΔY
/ Δy). That is, the pixel size Δx of the pixel of the image 405 in the x direction is defined as ｛(e / a) · (nx / N
x)｝ times, the size in the y direction The pixel size Δy is ｛(f
/ B) × (ny / NY)｝ multiplied image 405 ′ is created. At this time, the size of the image 405 ′ in the x direction is ｛e ·
(Nx / Nx)}, the size in the y direction is {f · (ny / N
Y)｝.

In general, nx ≠ Nx, ny ≠ NY, and
In addition, the position of the reference point in the image 405 'and the position of the tomographic image 40
7, the center position of the MRI marker is different.
When the 5 ′ and the tomographic image 407 are combined, a process of matching the position of the reference point with the center position of the MRI marker is performed between the two images, and the image 40 overlapping the tomographic image 407 is processed.
Only the pixel at 5 'is set as the target of synthesis.

Next, the image 405 ′ is added to the tomographic image
The center position of the RI marker 408 and the center position of the reference point 37 (the position (x, y) of the position 404 of the xiphoid process in the coordinate system (x, y, z) of the biomagnetic device) are matched. Overlap. At this time, the tomographic image 407 is stored in the storage memory.
And the data of the image 405 ′ are stored in the storage memory in association with each other, and the data of the plurality of tomographic images parallel to the tomographic image 407 and the data of the image 405 ′ are stored together with the tomographic image 407. Store in memory. Tomographic image 4
The center position of the MRI marker 408 of the tomographic image 407 is projected onto a plurality of tomographic images parallel to 07 and stored in the storage memory.

Next, the image 405 ′ containing the white arrow indicating the active site 406 and the tomographic image 409 stored in the storage memory are read out and synthesized as one image data.
A composite image 410 is created. Open X mark 4 shown in FIG.
The position of the white X mark 400'-1 where 00-1 is enlarged and the position of the white + sign 408'-1 where the white + mark 408-1 shown in FIG. The arrow 406-1 shown in FIG.
1, and an active site 40 indicated by a white arrow shown in FIG.
The white arrow 40 in which the white arrow representing 6 is enlarged.
6 ′, a composite image 410 including the tomographic image is displayed. When displaying the combined image, for example, the image 405 'and the tomographic image 409 are displayed in different colors.

According to the above-described method of creating a composite image, the center position of the MRI marker 408 of the tomographic image 407 is projected on a plurality of tomographic images parallel to the tomographic image 407 on the storage memory. Since the image 405 ′ and a tomographic image other than the tomographic image 409 can be easily synthesized, the relative positional relationship between each part of the heart and the active site 406 can be easily understood. When a plurality of active sites 406 are detected, the processing described above may be executed for each active site 406.

In the above description, a tomographic image by an MRI apparatus has been described as an example of a morphological image. However, instead of a tomographic image by an MRI apparatus, a tomographic image by an MRI apparatus representing a blood flow state may be used. (Second Embodiment) FIG. 8 shows a second embodiment of the present invention.
Synthetic image 601 with tomographic image (morphological image) by I device
FIG. 4 is a diagram showing an example of a display screen on a display device of the biomagnetic field measurement device. In the same manner as in the first embodiment, the process of matching the pixel size of the image representing the isomagnetic field map with the pixel size of the tomographic image and the center position of the reference point in the isomagnetic field map (biological Match the position of the measurement plane through which the z-axis of the coordinate system (x, y, z) of the magnetic field measuring device passes) with the reference point (the center position of the MRI marker image) photographed in the tomographic image And processing.

In the first embodiment, instead of the image 405, an isomagnetic field diagram connecting points having the same magnetic field strength measured at a certain time by a plurality of SQUID magnetometers is used, and FIG. An arbitrary tomographic image can be selected from a plurality of tomographic images parallel to the tomographic image 407 shown, and a composite image 601 of the selected arbitrary tomographic image and the isomagnetic field map can be created and displayed on a display device.

In FIG. 8, a thick line indicates a tomographic image obtained by the MRI apparatus, and a thin line indicates an isomagnetic field diagram in the measurement region 600 in the biomagnetic field measuring apparatus. Various contents can be displayed on the display screen of the display device. For example, a tomographic image can be successively changed in the depth direction, selected and designated by a mouse or the like, and a composite image of the tomographic image and the isomagnetic field diagram at a plurality of different depth positions can be displayed. In addition, a composite image of an ever-changing isomagnetic field map and a tomographic image selected from a plurality of tomographic images using a mouse or the like can be displayed, and a constantly changing isomagnetic field map superimposed on the selected tomographic image can be displayed. Significant diagnostic information can be obtained by comparing the morphological information shown in the image with the status of the change of the isomagnetic field map, which is the functional information.

FIG. 9 shows a second embodiment of the present invention, in which an arrow map obtained by a biomagnetic field measuring apparatus and an MRI are used.
Of the composite image 702 with the tomographic image (morphological image)
It is a figure showing an example of a display screen in a display of a biomagnetic field measuring device. The example shown in FIG. 9 uses an arrow map that displays the activated part of the heart to be examined as a two-dimensional current distribution instead of the isomagnetic field diagram in the example shown in FIG.

In FIG. 9, a thick line indicates a tomographic image by the MRI apparatus, an arrow indicates an arrow map, and the contents displayed on the display screen of the display device can be variously similar to FIG. For example, the time change of the arrow map can be displayed together with the selected tomographic image.

FIG. 10 shows a second embodiment of the present invention.
Isomagnetic field integral diagram and MRI obtained by biomagnetic field measurement device
Of the composite image 701 with the tomographic image (morphological image)
It is a figure showing an example of a display screen in a display of a biomagnetic field measuring device. The example shown in FIG. 10 is different from the example shown in FIG. 8 in that an integral strength is obtained by integrating a magnetic field waveform in a time section including a specific time phase of the heart activity instead of the isomagnetic field map. Integral magnetic field diagram connecting coordinate points with strength, or the time interval including two different time phases, by integrating the magnetic field waveforms of the tangential magnetic field components in the time section containing two different time phases to obtain the integrated strength The isomagnetic field integral diagram connecting the coordinate points having the same value of the difference of the integral intensity in the section is used.

In FIG. 10, a thick line indicates a tomographic image obtained by the MRI apparatus, a thin line indicates an iso-magnetic field integral diagram, and the contents displayed on the display screen of the display device are variously possible as in FIG. is there. For example, an isomagnetic field integral diagram can be displayed together with tomographic images at a plurality of different depth positions.

FIG. 11 shows a second embodiment of the present invention.
FIG. 7 is a diagram showing an example of a display screen on a display device of a biomagnetic field measurement apparatus, showing a composite image 801 of an activated site and isomagnetic field diagram obtained by the biomagnetic field measurement apparatus and a tomographic image (morphological image) obtained by an MRI apparatus. is there. The example shown in FIG. 11 is an example in which a composite image of three images of an isomagnetic field map, an image representing an activated site, and a tomographic image by an MRI apparatus is displayed. , The fault including the activation site is displayed together with the isomagnetic field map and the activation site. In FIG. 11, a thick line indicates a tomographic image obtained by the MRI apparatus, a thin line indicates an isomagnetic field diagram, and the contents displayed on the display screen of the display device are the same as in FIGS. 8, 9, and 10. Various possibilities are possible. For example, a composite image of three images representing an ever-changing isomagnetic field diagram, a tomographic image, and an activated portion can be displayed.

FIG. 12 shows a second embodiment of the present invention.
It is a figure showing an example of a display screen in a display of a biomagnetism measurement device of a synthetic picture 703 of an isomagnetic field map and an arrow map obtained by a biomagnetic measurement device, and a tomographic image (morphological image) by an MRI device. . The example shown in FIG. 12 is an example of displaying a combined image of three images of an isomagnetic field diagram, an arrow map, and a tomographic image obtained by an MRI apparatus, and an arrow map for displaying an activated site as a two-dimensional current distribution. It is displayed together with the magnetic field diagram. In FIG. 12, the thick line is the MRI
The tomographic image by the device is shown, the thin line shows the isomagnetic field map,
The arrow indicates the arrow map, and the contents displayed on the display screen of the display device can be variously similar to those shown in FIGS. 8, 9, and 10. For example, the constantly changing isomagnetic field map, tomographic image,
Also, a composite image of the three images of the arrow map and the arrow map can be displayed.

In the example shown in FIG. 8, it is also possible to display a combined image of the four images of the image showing the activated part, the isomagnetic field diagram, the arrow map, and the tomographic image by the MRI apparatus. Further, in the examples shown in FIG. 8, FIG. 9, FIG. 10, FIG. 11, and FIG.
Instead of this, a tomographic image by an MRI apparatus representing a blood flow state may be used. (Third Embodiment) FIG. 13 shows a third embodiment of the present invention, in which an isomagnetic field integral diagram measured with respect to an actual patient by a biomagnetic field measuring apparatus, and a tomographic image (morphological image) by an MRI apparatus. FIG. 6 is a diagram showing an example of a display screen of a composite image of the display device of the biomagnetic field measurement apparatus. The method of creating the composite image is performed by the method described in the first and second embodiments.

In the example shown in FIG. 13, the magnetic field waveforms are integrated in a time section including a time phase (time zone) in which the QRS wave of the heart activity appears and a time phase (time zone) in which T appears, and the integrated intensity is obtained. Is obtained, and an isomagnetic field integral diagram connecting coordinate points having the same value of the difference between the integral intensities in a time section including two different time phases is used.

In FIG. 13, a thick line indicates a tomographic image obtained by the MRI apparatus, a thin line indicates an isomagnetic field integral diagram, and the isomagnetic field integral diagram is displayed together with a tomographic image selected from a plurality of tomographic images. In FIG. 13, inactive portions 602 of myocardial activity in the patient's heart are indicated by black portions. In the inactive portion 602, the integral intensity is negative. The detection of the inactive part of the myocardial activity is considered to be very effective for the diagnosis of myocardial ischemia such as angina pectoris and myocardial infarction. (Fourth Embodiment) FIG. 14 shows a fourth embodiment of the present invention, in which an isomagnetic field map and an arrow map actually measured with respect to a patient by a biomagnetic field measuring apparatus and a tomographic image (form) by an MRI apparatus. FIG. 9 is a diagram showing an example of a display screen of a composite image of the biomagnetic field measurement device and a display image of the biomagnetic field measurement device. Note that the patient related to FIG. 13 is different from the patient related to FIG.
The method of creating the composite image is performed by the method described in the first and second embodiments.

In the example shown in FIG. 14, in the time phase (time zone) in which the P wave of the heart activity appears, the magnetic field strength in the tangential direction derived from the measured magnetic field component in the normal direction is equal. Use the isomagnetic field map connecting the coordinate points and the arrow map.

In FIG. 14, a thick line indicates a tomographic image by the MRI apparatus, a thin line indicates an isomagnetic field diagram in the measurement area 600, and an arrow indicates an arrow map. From FIG. 14 (a) to FIG.
4 (f) shows an actual measurement example of the time change of the isomagnetic field map displayed on the display screen of the display device. The isomagnetic field map is displayed together with one tomographic image selected from a plurality of tomographic images. I have. FIG. 14A to FIG. 14F show isomagnetic field diagrams showing the time lapse every 25 ms in the time phase in which the P wave appears.

As is evident from the change in the movement of the arrow in the arrow map shown in FIGS. 14A to 14F, a current (annular current) flowing around the left and right atria of the heart in a ring shape.
Is clearly shown to exist. The presence of this annular current is closely related to atrial tachycardia, and detection of the annular current is considered to be very effective in diagnosing atrial tachycardia. (Fifth Embodiment) In the first and second embodiments, M
Instead of a plurality of tomographic images by the RI device, various composite images can be created and displayed using a plurality of tomographic images obtained by the three-dimensional XCT device and substantially parallel to the chest surface. The processing for obtaining the composite image is the same as in the first and second embodiments, and the functional images (isomagnetic field diagram, arrow map, isomagnetic field integral diagram, activation site ( The function indicates the functional information on the activity of the heart such as the estimated position of the current source).) The process of matching the pixel size to the pixel size of the tomographic image obtained by the three-dimensional XCT device, The center position of the reference point in the obtained functional image (corresponding to the position of the measurement plane through which the z-axis of the coordinate system (x, y, z) of the biomagnetic field measurement device passes) and the reference position captured in the tomographic image Processing to match a point (the center point of the image of the X-ray marker). (Sixth Embodiment) In the first embodiment, instead of the tomographic image 407 by the MRI apparatus, the chest X by the X-ray imaging apparatus is used.
Using X-ray images (X-ray transmission images), chest X-ray images and functional images (isomagnetic field diagrams, arrow maps, isomagnetic field integral diagrams, activation sites (current sources)) obtained from biomagnetic field measurement devices Various types of composite images can be created and displayed with the function information related to the activity of the heart such as the estimated position. The process for obtaining the composite image consists of the process of matching the pixel size of the functional image obtained from the biomagnetic field measurement device to the pixel size of the chest X-ray image, and the process of obtaining the functional image obtained from the biomagnetic field measurement device. Of the reference point (first reference point) at the center (corresponding to the position of the measurement plane through which the z-axis of the coordinate system (x, y, z) of the biomagnetic field measuring device passes) and the chest X-ray image Processing to match the specified first reference point (the center point of the image of the X-ray marker), and rotating the chest X-ray image around the first reference point to obtain the chest X-ray image. The processing includes matching the direction of the body axis of the inspection target with the arrangement direction of the pixels in the body axis direction of the inspection target (the direction connecting the first reference point and the second reference point) in the functional image.

A composite image of a functional image and an image obtained by rotating the chest X-ray image around a first reference point (the center point of the image of the X-ray marker) can be created. An accurate composite image can be created. For example, the morphological image is set to the first reference point (X-ray marker) so that the center line of the spine in the chest X-ray image and the arrangement direction of the pixels in the body axis direction of the inspection target in the functional image are matched. (The center point of the image) can be rotated to create a more accurate composite image of the functional image and the morphological image.

In each of the embodiments described above, in the measurement by the biomagnetic field measuring apparatus, markers (for example, lead (size 5 mm × 5 mm, thickness 5 mm), vitamin agent ( A size of 5 mm × 5 mm, a thickness of 5 mm) or the like is used. In imaging of a tomographic image or a blood flow image by an MRI apparatus, a vitamin agent (size 5 mm × 5 mm, thickness 5 mm) is used as an MRI marker at the reference point 37.
Is attached. The vitamin preparation is displayed on an image taken by the MRI apparatus. In radiography of a chest X-ray image by an X-ray imaging device and tomographic image by a three-dimensional X-ray CT device, for example, lead (5 m in size) is used as an X-ray marker at the reference point 37.
(m × 5 mm, thickness 5 mm) or the like. Lead is chest X
It is displayed on a line image and an X-ray CT tomographic image. If it is difficult to identify the xiphoid process on the chest X-ray image, the distance between the cervical notch to be inspected and the xiphoid process is measured with a ruler, for example, and the measured cervical incision is measured. For the distance between the scar and the xiphoid process, a correction distance was calculated by correcting the effect of the radiographic magnification of the chest X-ray image, and on the chest X-ray image, along the central axis of the test object from the cervical notch Assuming that the xiphoid process exists at a position separated by the correction distance, the position of the xiphoid process can be determined.

In each of the embodiments described above, M
The data of the tomographic image and the blood flow image by the RI device are taken into the storage device of the biomagnetic field measuring device, and the data of the chest X-ray image by the X-ray imaging device and the data of the tomographic image data by the three-dimensional XCT device are obtained. The magnetic field measurement device is loaded into the storage device by the following method.

Biomagnetic field measuring device, MRI device, 3D X
CT scanners, image reading devices that digitize the density of the film on the chest X-ray image and read it as image data, etc.
PACS (Picture Archiving an
d Communications Systems
, The image data is read online from each device to the storage device of the biomagnetic field measurement device.

Further, an MRI device, a three-dimensional XCT device, X
When an image obtained by a radiographic device or the like is obtained on a film, the digitized image data is stored in a portable medium using an image reading device that digitizes the density of the film and reads it as image data. Thus, the image data is read into the storage device of the biomagnetic field measurement device via a portable medium. Alternatively, a configuration may be adopted in which the image reading device and the biomagnetic field measuring device are connected online, and output data (digitized image data) of the image reading device is directly taken into the storage device of the biomagnetic field measuring device.

FIG. 15 is a schematic diagram showing an example of a procedure for creating a composite image of a biological function image and a morphological image in each embodiment of the present invention. The procedure will be summarized below with reference to FIG.

Step 1 (reference numeral 71): MRI apparatus, 3
A morphological image including the chest is captured by a three-dimensional X-ray CT apparatus, an X-ray imaging apparatus, or the like. In imaging with an MRI apparatus or a three-dimensional X-ray CT apparatus, a plurality of tomographic images parallel to the surface of the chest to be inspected are captured. In the X-ray imaging apparatus, a chest X-ray image (X-ray transmission image) taken from the front is taken. In photographing these morphological images, a first marker indicating a first reference point is arranged on the body surface of the xiphoid process to be inspected.

Step 2 (reference number 72): The morphological image photographed in step 1 (reference number 71) is selected.

Step 3 (reference numeral 73): A first marker indicating a first reference point is placed on the body surface of the xiphoid process to be inspected, and a second reference point is placed on the body surface of the cervical notch to be tested. Each of the second markers shown is attached, and the magnetic field component in the normal direction of the magnetic field generated from the heart is measured.

Step 4 (reference numeral 74): Estimate the tangential magnetic field component of the magnetic field generated from the heart from the measured normal magnetic field component, and use the tangential magnetic field component to determine the activity of the heart. A function image (isomagnetic field diagram, arrow map, isomagnetic field integral diagram, estimated position of current source, etc.) representing function information is created.

Step 5 (reference number 75): The functional image created in step 4 (reference number 74) is selected.

Step 6 (reference numeral 76): A process for matching the element size of the functional image with the pixel size of the morphological image is performed.

Step 7 (reference numeral 77): First of functional image
And the first reference point of the morphological image are made to coincide with each other.

Step 8 (reference numeral 78): If the body axis direction of the inspection target in the morphological image does not match the pixel arrangement direction in the body axis direction of the inspection target in the functional image, the morphological image is deleted. A rotation is performed about the first reference point, and processing is performed to match the direction of the body axis of the inspection target in the morphological image with the arrangement direction of the pixels in the body axis direction of the inspection target in the functional image.

Step 9 (reference numeral 79): The functional image and the morphological image are combined into one image to obtain a combined image.

Step 1 (reference numeral 71) and step 3
(Reference numeral 73) may be executed first. In step 5 (reference number 75), a plurality of functional images created in step 4 (reference number 74) are selected, and
By (reference number 76) to step 9 (reference number 79), a composite image of a plurality of functional images and morphological images may be created and displayed. Furthermore, a plurality of functional images and, for example, process 1
(Reference numeral 71) A composite image of each of a plurality of tomographic images selected from a plurality of tomographic images taken in parallel with the plane of the chest to be inspected may be displayed. The execution of step 8 (reference numeral 78) may be omitted.

As described above, according to the present invention, an isomagnetic field map, an arrow map, an isomagnetic field integral diagram, an activation site, which can be obtained by a biomagnetic field measuring apparatus in a short time without requiring complicated calculations. The size of the pixel of the functional image representing the functional information on the activity of the heart such as the estimated position of the (current source)
Processing to match the pixel size of the morphological image representing the morphology of the heart obtained by an MRI apparatus, a three-dimensional XCT apparatus, an X-ray imaging apparatus, etc., and the center position of the first reference point in the functional image (biomagnetic field) Z of the coordinate system (x, y, z) of the measuring device
The first reference point (the center point of the image of the MRI marker,
Or a process of matching the center point of the image of the X-ray marker).

Further, the morphological image is rotated around the first reference point (the center point of the image of the MRI marker or the center point of the image of the X-ray marker) photographed in the morphological image, and the morphological image is rotated. A process of matching the direction of the pixel axis in the body axis direction of the test object in the functional image with the direction of the body axis of the test object in the functional image (the direction connecting the first reference point and the second reference point); A more accurate composite image of the functional image and the morphological image can be created.

As a result, in the present invention, the MRI apparatus or 3
An arbitrary tomographic image is selected from a plurality of tomographic images substantially parallel to the chest surface obtained by a three-dimensional XCT apparatus or the like, and the selected tomographic image is combined with a time-varying isomagnetic field map or a time-varying arrow map. Images can be displayed every moment.

An image showing the activation site and an MRI
Display of a composite image of a tomographic image that is substantially parallel to the chest surface and that contains an active site, and a time-varying isomagnetic field diagram or a time-varying isomagnetic field integral diagram obtained by a device or a three-dimensional XCT device it can. The image representing the activation site is represented, for example, by an arrow, where the root position of the arrow indicates the estimated position of the current source, the length of the arrow indicates the size of the current source, and the direction of the arrow is (x, y) shows the direction of the vector representing the current source projected onto the plane.

Further, a composite image of a chest X-ray image (morphological image) by the X-ray imaging apparatus and a time-varying isomagnetic field diagram or a time-varying isomagnetic field integral diagram can be displayed every moment.
Further, a composite image of a chest X-ray image (X-ray transmission image), an image representing an activated part, and a time-varying isomagnetic field diagram or a time-varying isomagnetic field integral diagram can be displayed every moment.

[0127]

According to the present invention, in particular, when detecting a magnetic field emanating from the heart to be examined, almost the entire projection of the heart onto the surface of the sensor array is located within the area of the sensor array, The operation of bringing the body surface of the chest into contact with the lower surface of the Dua to obtain a large signal output can be realized in a short time and easily.

According to the present invention, the biological function information obtained by the biomagnetic field measurement apparatus, particularly from the heart, is not executed, without executing complicated calculations such as simulation calculation of magnetic field generation and calculation of reconstruction of tomographic images. Isomagnetic field maps, arrow maps, and magnetic fields obtained from the magnetic field waveform obtained by measuring the generated magnetic field
Functional information related to the activity of the heart represented by an isomagnetic field integral map, a result of position estimation of a current dipole, and a morphological image substantially parallel to the chest plane obtained by a nuclear magnetic resonance (MRI) device, a three-dimensional XCT device, or the like ( A composite image with a tomographic image or a transmission image such as a chest X-ray image obtained by an X-ray imaging apparatus can be easily created and displayed.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of the overall configuration of a biomagnetic field measuring apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram for explaining details of a configuration example of the biomagnetic field measurement apparatus according to the first embodiment of the present invention.

FIG. 3 is a schematic diagram showing an example of a procedure for arranging an inspection target mounted on a bed on a lower surface of a dual according to the first embodiment of the present invention.

FIG. 4 is a diagram illustrating adjustment of irradiation directions of three lasers used when arranging an inspection target mounted on a bed on a lower surface of a dual according to the first embodiment of the present invention.

FIG. 5 is an example of a display screen of information obtained by the biomagnetic field measuring apparatus according to the first embodiment of the present invention, showing a display example of an image representing an estimated position of an active site.

FIG. 6 is a diagram showing an example of a display screen showing a position of a tomographic image by an MRI apparatus which is combined with an image representing an estimated position of an active part obtained by a biomagnetic field measuring apparatus in the first embodiment of the present invention.

FIG. 7 shows an image representing an estimated position of an active part obtained by the biomagnetic field measuring apparatus and M according to the first embodiment of the present invention.
FIG. 4 is a diagram showing a display example of a composite image with a tomographic image obtained by an RI device.

FIG. 8 is a diagram illustrating a display example of a composite image of an isomagnetic field diagram obtained by a biomagnetic field measuring apparatus and a tomographic image by an MRI apparatus according to a second embodiment of the present invention.

FIG. 9 is a diagram illustrating a display example of a composite image of an arrow map obtained by a biomagnetic field measurement apparatus and a tomographic image by an MRI apparatus according to a second embodiment of the present invention.

FIG. 10 is a diagram illustrating a display example of a combined image of an iso-magnetic field integral diagram obtained by a biomagnetic field measurement device and a tomographic image by an MRI device according to a second embodiment of the present invention.

FIG. 11 shows a second embodiment of the present invention, in which an activation site and an isomagnetic field map obtained by a biomagnetic field measuring apparatus are used;
The figure which shows the example of a display of the synthetic | combination image with the tomographic image by I apparatus.

FIG. 12 shows a second embodiment of the present invention, in which an isomagnetic field map and an arrow map obtained by a biomagnetic field measuring apparatus and M
FIG. 4 is a diagram showing a display example of a composite image with a tomographic image by the RI device.

FIG. 13 shows a third embodiment of the present invention, in which a display screen of a display device of a combined image of an isomagnetic field integral diagram measured for an actual patient by a biomagnetic field measuring device and a tomographic image by an MRI device is displayed. The figure which shows an example.

FIG. 14 shows a fourth embodiment of the present invention, which is a display device for displaying a composite image of an isomagnetic field map and an arrow map actually measured with respect to a patient by a biomagnetic field measuring apparatus and a tomographic image by an MRI apparatus. The figure which shows the example of a display screen.

FIG. 15 is a schematic diagram showing an example of a procedure for creating a composite image of a biological function image and a morphological image in each embodiment of the present invention.

FIG. 16 is a view for explaining an example of the prior art for specifying the position coordinates of the position of the head in the biomagnetic field measurement for measuring the brain magnetic field.

FIG. 17 is a view for explaining an example of the prior art in which the position coordinates of a marker are specified using an MRI image in order to synthesize a measurement result of a brain magnetic field and an MRI image of a head.

[Explanation of symbols]

2: magnetic shield room, 6: drive circuit, 7: amplifier filter unit, 8: computer, 11: bottom of the dual, 1
2: Detection coil, 13: Magnetic field generation coil, 21: MRI
Marker, 35: inspection object, 31: bed, 31-1: bed holder, 31-2: feed rail, 31-3: left and right feed handle, 31-4: hydraulic pump handle, 36 ...
Dua (cryogenic container), 36-1 ... xz label, 36-2 ...
yz sign, 32 ... left-right direction (y-axis direction), 33 ... front-back direction (x-axis direction), 34 ... up-down direction (z-axis direction), 37,
38: Reference point, 39: Long axis direction of bed, 40: Laser (second laser), 41: Laser oscillator (Second laser light source), 41-1: Oscillator holder, 41-2: On bed holder Fixed pipe frame, 42: short axis direction of bed, 43: laser (first laser), 44: laser oscillator (first laser light source), 44-1: oscillator holder,
44-2: Pipe frame fixed to gantry, 4
5: Ultrasonic displacement sensor for measuring displacement from the floor of the bed, 46: Gantry, 47: Laser (third laser), 48: Laser oscillator (third laser light source), 48
-1 ... oscillator holder, 48-2 ... pipe frame fixed to the floor, 400 ... sensor arranged at a specific position (SQ
UID flux meter), 400'-1 ...
Mark, 401: Measurement surface parallel to bed, 402: Multiple sensors (SQUID magnetometer), 403: Surface at depth c parallel to measurement surface, 404: Position of xiphoid projection, 405: Parallel to measurement surface 406... A white arrow indicating an active site, 406 ′... A white arrow, 406 ′ -1... An enlarged arrow, 405 ′... A pixel size corrected image, 407. Tomographic image, 408 ... MRI marker, 408-
Reference numeral 1 denotes a white + mark, 408'-1 ... an enlarged white + mark, 409 denotes a tomographic image, 600 denotes a measurement area, 602 denotes an inactive portion of myocardial activity, 410, 601, 701, and 70.
2, 703, 801: Composite image.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Akihiko Kamtori 1-280 Higashi Koigakubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory of Hitachi, Ltd. Within the measuring instruments group (72) Inventor Hitoshi Sasabuchi 882 Ma, Hitachinaka-shi, Ibaraki Prefecture Within the measuring instruments group of Hitachi, Ltd.

Claims (6)

[Claims] 1. A bed, a plurality of SQUID magnetometers respectively arranged in an x direction and ay direction, and the plurality of SQ magnetometers.
A biomagnetic field measuring apparatus having a UID magnetometer cooled, and having, on the outer peripheral surface of the bottom thereof, an xz marker representing an xz plane of a coordinate system (x, y, z) and a cryogenic container having a yz marker representing a yz plane. The method of positioning the inspection target for (1) x
setting the irradiation direction of the first fan-shaped laser so that the first fan-shaped laser spreading in a z-plane irradiates the xz marker; and (2) a second fan-shaped spreading in the yz-plane. The second laser is applied so that the sector laser illuminates the yz marker.
Setting the irradiation direction of the fan-shaped laser of (3), and (3) a point-shaped laser irradiated to the surface of the bed from an oblique direction so as to intersect the first and second fan-shaped lasers. A beam is transmitted between the first fan-shaped laser and the second fan-shaped laser.
Setting the irradiation direction of the point-like laser beam so as to irradiate the intersection line of the fan-shaped laser and the intersection of the z-axis with the surface of the bed; (4) within the yz plane The second fan-shaped laser includes a first reference point indicated by a first marker disposed on a body surface of a first point on a chest to be inspected, and a body at a second point on the chest to be inspected. Setting the irradiation direction of the second fan-shaped laser so as to pass through a second reference point indicated by a second marker arranged on the surface; and (5) the second fan-shaped laser emits the yz marker. And (6) moving the bed in the y direction so that the first fan-shaped laser passes through the first reference point in the yz plane. Moving the first reference point and the second reference point. A biomagnetic field measuring apparatus, wherein the chest to be inspected is arranged at a lower portion of a bottom surface of the cryocontainer such that a line coincides with or is parallel to one direction in which the center of the SQUID magnetometer is arranged. Method of positioning the inspection target for the purpose. 2. The positioning method according to claim 1, wherein
(7) a step of moving the bed in the z-direction until the irradiation point of the point-like laser beam coincides with the first reference point; and (8) the body surface of the inspection object has the low temperature. Moving the bed in the z-direction until it comes into contact with the bottom surface of the container to determine the distance between the first reference point and the bottom surface of the low-temperature container. Inspection target positioning method. 3. The positioning method according to claim 1, wherein
The method according to claim 1, wherein the first point is a xiphoid process of the test object, and the second point is a cervical notch of the test object. 4. A bed, a plurality of SQUID magnetometers respectively arranged in the x and y directions, and the plurality of SQ magnetometers.
The UID magnetometer is cooled, and a low-temperature container having an xz mark indicating the xz plane of the coordinate system (x, y, z) and a yz mark indicating the yz plane on the outer peripheral surface of the bottom, and a low-temperature fixed to the floor surface A gantry holding the container, a first laser source for generating a first fan-shaped laser fan-shaped in the xz plane, and y
a second fan generating a second fan-shaped laser fan-shaped in the z-plane
And a third laser source for generating a point-like laser beam irradiating the surface of the bed from an oblique direction so as to intersect the first and second fan-shaped lasers, The first laser source is fixed to a frame fixed to the gantry, the second laser source is fixed to a frame fixed to the holding table, and the third laser source is mounted on the floor or ceiling. The positioning method of the inspection object for the biomagnetic field measurement device fixed to the fixed frame is as follows.
(1) setting the irradiation direction of the first fan-shaped laser so that the first fan-shaped laser irradiates the xz mark; and (2) irradiating the yz mark with the second fan-shaped laser. Setting the irradiation direction of the second fan-shaped laser as described above; and (3) the point-shaped laser beam is a line at which the first fan-shaped laser and the second fan-shaped laser intersect.
And setting the irradiation direction of the point-like laser beam so as to irradiate the intersection of the z-axis and the surface of the bed; and (4) the second fan-shaped laser in the yz plane includes: A first reference point indicated by a first marker located on the body surface at a first point on the chest to be inspected, and a second reference point located on the body surface at a second point on the chest to be inspected Setting an irradiation direction of the second fan-shaped laser so as to pass through a second reference point indicated by a marker; and (5) setting the bed such that the second fan-shaped laser irradiates the yz mark. moving the bed in the y direction so that the first fan-shaped laser passes through the first reference point in the yz plane; and
The chest to be inspected is placed on the cryogenic container such that a line connecting the first reference point and the second reference point coincides or is parallel to one direction in which the centers of the SQUID magnetometers are arranged. A method for positioning an inspection target for a biomagnetic field measuring apparatus, wherein the method is arranged below a bottom surface. 5. The positioning method according to claim 4, wherein
(7) a step of moving the bed in the z-direction until the irradiation point of the point-like laser beam coincides with the first reference point; and (8) the body surface of the inspection object has the low temperature. Moving the bed in the z-direction until it comes into contact with the bottom surface of the container to determine the distance between the first reference point and the bottom surface of the low-temperature container. Inspection target positioning method. 6. The positioning method according to claim 4, wherein
The method according to claim 1, wherein the first point is a xiphoid process of the test object, and the second point is a cervical notch of the test object.