JPH09164123A - Biomagnetic measurement device - Google Patents
Biomagnetic measurement deviceInfo
- Publication number
- JPH09164123A JPH09164123A JP7347607A JP34760795A JPH09164123A JP H09164123 A JPH09164123 A JP H09164123A JP 7347607 A JP7347607 A JP 7347607A JP 34760795 A JP34760795 A JP 34760795A JP H09164123 A JPH09164123 A JP H09164123A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic field
- field component
- isomagnetic
- component
- horizontal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
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- Measurement And Recording Of Electrical Phenomena And Electrical Characteristics Of The Living Body (AREA)
Abstract
(57)【要約】
【課題】 生体活動電流源の個数や位置などを総合的に
判断するのに適した等磁界線図を得ることができる生体
磁気計測装置を提供する。
【解決手段】 被検体Ｍに近接配備されたマルチチャン
ネルＳＱＵＩＤセンサ１２で、生体活動電流源による微
小磁界の直交３軸成分を測定し、その測定データから磁
界成分算出部１８で各測定点における垂直磁界成分と水
平２方向の磁界成分とを算出し、補間処理部１９で測定
面上の多数の格子点における垂直磁界成分と水平２方向
の合成磁界成分を求め、等磁界線図作成部２０で垂直磁
界成分の等磁界線図を作成し、さらに合成処理部２１で
前記等磁界線図上に水平２方向の合成磁界成分のベクト
ルの矢印表示の分布を重ね合わせる。
(57) Abstract: A biomagnetism measuring device capable of obtaining an isomagnetic field map suitable for comprehensively determining the number and positions of bioactive current sources. SOLUTION: A multi-channel SQUID sensor 12 arranged close to a subject M measures orthogonal three-axis components of a minute magnetic field generated by a biological activity current source, and a magnetic field component calculator 18 uses the measured data to determine the vertical direction at each measurement point. The magnetic field component and the horizontal two-direction magnetic field component are calculated, the vertical magnetic field component and the horizontal two-direction combined magnetic field component at a large number of grid points on the measurement surface are calculated by the interpolation processing unit 19, and the constant magnetic field map creation unit 20 is obtained. An isomagnetic field map of the vertical magnetic field component is created, and the composition processing unit 21 superimposes the distributions of the vectors of the composite magnetic field components in the two horizontal directions indicated by arrows.
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、生体から発生す
る微弱な磁気を検出し、これを画像化することによっ
て、医学上有用な診断情報を提供する生体磁気計測装置
に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biomagnetism measuring apparatus for providing medically useful diagnostic information by detecting a weak magnetism generated from a living body and imaging it.
【０００２】[0002]
【従来の技術】生体に刺激を与えると、細胞膜を挟んで
形成されている分極が壊れて生体活動電流が流れる。こ
の生体活動電流は、脳や心臓において現れ、脳波，心電
図として記録される。また、生体活動電流によって生じ
る磁界は、脳磁図，心磁図として記録される。2. Description of the Related Art When a living body is stimulated, the polarization formed across a cell membrane is broken and a living activity current flows. This biological activity current appears in the brain and heart, and is recorded as an electroencephalogram and an electrocardiogram. The magnetic field generated by the biological activity current is recorded as a magnetoencephalogram and a magnetocardiogram.
【０００３】近年、生体から発せられる微弱な磁気を検
出する装置として、ＳＱＵＩＤ（Superconducting Quan
tum Interface Device：超電導量子干渉計）素子を用い
たＳＱＵＩＤセンサが開発された。図１２に示すよう
に、ＳＱＵＩＤセンサ１は、差動結合された検出コイル
２と補償コイル３とを図示しないＳＱＵＩＤ素子に接続
して構成されている。各コイル２，３を差動結合するの
は、地磁気などのように無限遠にあるとみなされるノイ
ズを除去するためである。このＳＱＵＩＤセンサ１は液
体ヘリウムなどの冷媒に浸漬して用いられる。また、最
近では図１３に示すように、液体ヘリウムなどの冷媒を
満たしたデュワーと呼ばれる冷媒容器４内に、複数個の
ＳＱＵＩＤセンサ１を球面上に配置して構成されたマル
チチャンネルＳＱＵＩＤセンサが用いられている。In recent years, SQUID (Superconducting Quan) has been used as a device for detecting a weak magnetic field emitted from a living body.
A SQUID sensor using a tum interface device (superconducting quantum interferometer) element was developed. As shown in FIG. 12, the SQUID sensor 1 is configured by connecting the differentially coupled detection coil 2 and compensation coil 3 to an SQUID element (not shown). The reason why the coils 2 and 3 are differentially coupled is to remove noise that is considered to be at infinity, such as geomagnetism. This SQUID sensor 1 is used by being immersed in a coolant such as liquid helium. Further, recently, as shown in FIG. 13, a multi-channel SQUID sensor configured by arranging a plurality of SQUID sensors 1 on a spherical surface in a refrigerant container 4 called a Dewar filled with a refrigerant such as liquid helium is used. Has been.
【０００４】上記のようなＳＱＵＩＤセンサ１を診断対
象部位である被検体Ｍの頭部に近接配備することによ
り、頭部内の生体活動電流源によって生じた磁界の直交
３軸成分（Ｂｒ，Ｂθ，Ｂφ）のうち、ＳＱＵＩＤセン
サ１のコイル軸芯方向の垂直成分Ｂｒを検出することが
できる。各ＳＱＵＩＤセンサ１が配置された測定点にお
ける磁界の垂直成分が求められると、これらの測定点を
含む測定面上の多数の格子点の磁界成分をスプライン補
間などによって求め、このうち同じ磁界強度の格子点を
順次連結することにより図１４に示すような垂直磁界成
分の等磁界線図が得られる。この図１４に示した等磁界
線図は単一の電流双極子（電流源）によって生じた磁界
を検出して得られたものであって、図中の白丸は測定
点、黒丸は補間によって磁界成分が算出される測定面上
の多数の格子点である。この等磁界線図によれば、正
（＋）と負（−）の磁場ピークのほぼ中央に現れる零線
（磁場強度がほぼ零になる線）上に電流源（太い矢印で
示す）があると推定される。By disposing the SQUID sensor 1 as described above in the vicinity of the head of the subject M, which is the site to be diagnosed, orthogonal three-axis components (Br, Bθ) of the magnetic field generated by the biological activity current source in the head are provided. , Bφ), the vertical component Br in the coil axis direction of the SQUID sensor 1 can be detected. When the vertical component of the magnetic field at the measurement point where each SQUID sensor 1 is arranged is obtained, the magnetic field components at a large number of grid points on the measurement surface including these measurement points are obtained by spline interpolation or the like, and the same magnetic field strength By sequentially connecting the lattice points, an isomagnetic field diagram of vertical magnetic field components as shown in FIG. 14 can be obtained. The contour diagram shown in FIG. 14 is obtained by detecting a magnetic field generated by a single current dipole (current source). White circles in the figure represent measurement points and black circles represent magnetic fields by interpolation. It is a large number of grid points on the measurement surface whose components are calculated. According to this isomagnetic field diagram, the current source (indicated by a thick arrow) is located on the zero line (the line at which the magnetic field strength becomes almost zero) that appears in the approximate center of the positive (+) and negative (-) magnetic field peaks. It is estimated to be.
【０００５】[0005]
【発明が解決しようとする課題】しかしながら、このよ
うな構成を有する従来例の場合には、次のような問題が
ある。すなわち、診断対象部位内に複数個の電流源が存
在すると、そのとき得られる垂直磁界成分の等磁界線図
は、図１４に示したような単一電流源の垂直磁界成分の
等磁界線図を数種類重ね合わせたような複雑な線図にな
る。このような垂直磁界成分の等磁界線図から各電流源
の個数や位置などを特定することは非常に困難である。However, the prior art having such a structure has the following problems. That is, when a plurality of current sources exist in the diagnosis target region, the isomagnetic field diagram of the vertical magnetic field component obtained at that time is the isomagnetic field diagram of the vertical magnetic field component of the single current source as shown in FIG. It is a complicated diagram that looks like several different types are superposed. It is very difficult to specify the number and position of each current source from the contour lines of such a vertical magnetic field component.
【０００６】このような垂直磁界成分の等磁界線図がも
つ不具合を解消した等磁界線図として、本出願人は先
に、水平合成磁界成分の等磁界線図が得られる生体磁気
計測装置を提案している（特願平７−１００３３８
号）。この生体磁気計測装置は、被検体Ｍの診断対象部
位に近接配備された複数個の磁気センサによって検出さ
れた各測定点における磁界の直交３軸成分（Ｂｒ，Ｂ
θ，Ｂφ）のうち、前記の垂直磁界成分Ｂｒに直交する
水平２方向の磁界成分Ｂθ，Ｂφを検出し、各測定点を
含む測定面上の多数の格子点の水平合成磁界成分をスプ
ライン補間などによって求め、このうち水平合成磁界成
分の大きさが同じ格子点を順次連結することにより、図
１５に示すような水平合成磁界成分の等磁界線図を得て
いる。As an isomagnetic field map which eliminates the disadvantage of the isomagnetic field map of such a vertical magnetic field component, the present applicant has previously proposed a biomagnetism measuring device capable of obtaining an isomagnetic field map of a horizontal composite magnetic field component. Proposed (Japanese Patent Application No. 7-100338)
issue). This biomagnetism measuring apparatus includes orthogonal three-axis components (Br, B) of a magnetic field at each measurement point detected by a plurality of magnetic sensors arranged in proximity to a diagnosis target site of a subject M.
θ, Bφ), magnetic field components Bθ, Bφ in two horizontal directions orthogonal to the vertical magnetic field component Br are detected, and the horizontal composite magnetic field components of a large number of grid points on the measurement surface including each measurement point are spline-interpolated. For example, by sequentially connecting grid points having the same magnitude of the horizontal combined magnetic field component among them, an isomagnetic field map of the horizontal combined magnetic field component as shown in FIG. 15 is obtained.
【０００７】図１５に示した等磁界線図は、診断対象部
位に２つの電流源Ｐ1 ，Ｐ2 が存在したある場合に得ら
れた等磁界線図である。このような水平合成磁界成分の
等磁界線図によれば、等磁界線図に表れるピークの位置
が電流源の位置にほぼ対応するので、診断対象部位に複
数個の電流源が存在する場合にも、各電流源の個数や大
まかな位置を比較的容易に推定することができる。The isomagnetic field diagram shown in FIG. 15 is an isomagnetic field diagram obtained when two current sources P 1 and P 2 are present at the site to be diagnosed. According to such an isomagnetic field diagram of the horizontal combined magnetic field component, the position of the peak appearing in the isomagnetic field diagram almost corresponds to the position of the current source. Therefore, when there are a plurality of current sources at the diagnosis target site, Also, the number and rough position of each current source can be estimated relatively easily.
【０００８】そして、各電流源の個数や位置，大きさを
より一層精度よく推定するためには、従来から知られて
いる垂直磁界成分の等磁界線図と、本出願人によって先
に提案された上記の水平合成磁界成分の等磁界線図とを
見比べて総合的に判断するのが好ましいのであるが、別
々に出力表示された２つの等磁界線図を見比べるのは検
査者にとって煩雑であり、ともすれば的確かつ迅速に判
断を下せないこともあった。In order to more accurately estimate the number, position, and size of each current source, the conventionally known isomagnetic field diagram of the vertical magnetic field component and the applicant previously proposed. It is preferable to make a comprehensive judgment by comparing the above-mentioned horizontal magnetic field component isomagnetic field diagrams, but it is cumbersome for the inspector to compare the two isomagnetic field diagrams that are output and displayed separately. However, there were times when it was not possible to make accurate and quick decisions.
【０００９】この発明は、このような事情に鑑みてなさ
れたものであって、生体活動電流源の個数や位置などを
総合的に判断するのに適した等磁界線図を得ることがで
きる生体磁気計測装置を提供することを目的としてい
る。The present invention has been made in view of such circumstances, and it is possible to obtain an isomagnetic field map suitable for comprehensively determining the number and positions of biological activity current sources. It is intended to provide a magnetic measuring device.
【００１０】[0010]
【課題を解決するための手段】この発明は、このような
目的を達成するために、次のような構成をとる。すなわ
ち、この発明に係る生体磁気計測装置は、被検体の診断
対象領域に近接する各位置（測定点）に配備され、前記
診断対象領域内の生体活動電流源による微小磁界の直交
３軸成分を各測定点で計測する複数個の磁気センサと、
前記各磁気センサで計測された各測定点の磁界の直交３
軸成分から各測定点における垂直方向の磁界成分および
水平２方向の磁界成分を求める磁界成分算出手段と、前
記各測定点における垂直方向の磁界成分および水平２方
向の合成磁界成分に基づき、各磁気センサが置かれた測
定面上の多数の格子点における垂直磁界成分および水平
合成磁界成分を算出する補間処理手段と、磁界成分の大
きさの等しい格子点を順次連結することによって垂直磁
界成分または水平合成磁界成分のいずれか一方の等磁界
線図を求める等磁界線図作成手段と、垂直磁界成分の等
磁界線図を求めた場合には、この等磁界線図に各格子点
の水平合成磁界成分のベトクルの矢印表示を重ね合わせ
る一方、水平合成磁界成分の等磁界線図を求めた場合に
は、この等磁界線図に各格子点の垂直磁界成分に関連し
たベトクルの矢印表示を重ね合わせる合成処理手段と、
前記合成処理された等磁界線図を出力する出力手段と、
を備えたものである。The present invention has the following configuration to achieve the above object. That is, the biomagnetism measuring device according to the present invention is arranged at each position (measurement point) in the vicinity of the diagnosis target region of the subject, and determines the orthogonal triaxial components of the minute magnetic field by the biological activity current source in the diagnosis target region. Multiple magnetic sensors that measure at each measurement point,
Orthogonal 3 of the magnetic field of each measurement point measured by each magnetic sensor
Based on the magnetic field component calculating means for obtaining the vertical magnetic field component and the horizontal two-direction magnetic field component at each measurement point from the axial component, and the respective magnetic fields based on the vertical magnetic field component and the two horizontal horizontal direction magnetic field components at each measurement point. Interpolation means for calculating vertical magnetic field components and horizontal composite magnetic field components at a large number of grid points on the measurement surface on which the sensor is placed, and grid points having the same magnitude of the magnetic field component are sequentially connected to each other so that the vertical magnetic field component or the horizontal magnetic field component When an equal magnetic field map creating means for obtaining one of the combined magnetic field components of the combined magnetic field component and an equal magnetic field map of the vertical magnetic field component are obtained, the horizontal combined magnetic field of each grid point is added to this isolated magnetic field map. The component arrow marks of the components are superimposed, while the contour plot of the horizontal composite magnetic field component is obtained. And synthesis processing means for superimposing the view,
Output means for outputting the combined magnetic field contour map,
It is provided with.
【００１１】[0011]
【作用】この発明の作用は次のとおりである。先ず、複
数個の磁気センサを被検体の診断対象領域に近接する各
位置（測定点）に配備し、診断対象領域内の生体活動電
流源による微小磁界の直交３軸成分を各測定点で計測す
る。そして、磁界成分算出手段が前記各磁気センサで計
測された各測定点の磁界の直交３軸成分から各測定点に
おける垂直方向の磁界成分と水平２方向の磁界成分とを
求める。次に、補間処理手段が各測定点における垂直方
向の磁界成分と水平２方向の磁界成分とに基づき、各磁
気センサが置かれた測定面上の多数の格子点における垂
直磁界成分と水平合成磁界成分とを算出する。そして、
等磁界線図作成手段が、磁界成分の大きさの等しい格子
点を順次連結することによって垂直磁界成分または水平
合成磁界成分のいずれか一方の等磁界線図を求める。垂
直磁界成分の等磁界線図が求められた場合、合成処理手
段が、この等磁界線図に各格子点の水平合成磁界成分の
ベトクルの矢印表示を重ね合わせる。一方、水平合成磁
界成分の等磁界線図が求められた場合には、合成処理手
段が、この等磁界線図に各格子点の垂直磁界成分に関連
したベトクルの矢印表示を重ね合わせる。そして、出力
手段が合成処理された等磁界線図を出力する。The operation of the present invention is as follows. First, a plurality of magnetic sensors are arranged at respective positions (measurement points) close to the diagnosis target area of the subject, and orthogonal three-axis components of a minute magnetic field generated by the biological activity current source in the diagnosis target area are measured at the respective measurement points. To do. Then, the magnetic field component calculation means obtains a vertical magnetic field component and a horizontal two-direction magnetic field component at each measurement point from the orthogonal triaxial components of the magnetic field at each measurement point measured by each magnetic sensor. Next, the interpolation processing means, based on the vertical magnetic field component and the horizontal two-direction magnetic field component at each measurement point, the vertical magnetic field component and the horizontal composite magnetic field at a large number of grid points on the measurement surface on which each magnetic sensor is placed. And the components. And
The contour magnetic field map creation means obtains the contour magnetic field map of either the vertical magnetic field component or the horizontal composite magnetic field component by sequentially connecting the grid points having the same magnitude of the magnetic field component. When the isomagnetic field map of the vertical magnetic field component is obtained, the combining processing means superimposes the arrow mark of the vector of the horizontal composite magnetic field component of each lattice point on the isomagnetic field map. On the other hand, when the isomagnetic field map of the horizontal composite magnetic field component is obtained, the composition processing means superimposes the arrow mark of the vector associated with the vertical magnetic field component of each lattice point on the isomagnetic field map. Then, the output means outputs the combined magnetic field contour map.
【００１２】[0012]
【発明の実施の形態】以下、図面を参照してこの発明の
実施例を説明する。図１はこの発明に係る生体活動電流
源推定装置の一実施例の概略構成を示したブロック図で
ある。図中、符号１０は磁気シールドルームであり、こ
の磁気シールドルーム１０内に被検体Ｍが仰臥されるベ
ッド１１と、被検体Ｍの診断対象領域である例えば脳に
近接配備され、脳内に生じた生体活動電流源による微小
磁界を無侵襲に計測するためのマルチチャンネルＳＱＵ
ＩＤセンサ１２とが設けられている。マルチチャンネル
ＳＱＵＩＤセンサ１２は、デュワーと呼ばれる冷媒容器
内に複数個のＳＱＵＩＤセンサユニットを配置して液体
ヘリウムなどの冷媒に浸漬して収納している。各ＳＱＵ
ＩＤセンサユニットは磁界の直交３軸成分をそれぞれ計
測（ベクトル計測）する３つのＳＱＵＩＤセンサで構成
されている。ＳＱＵＩＤセンサユニットの具体的な構成
は後に詳述する。なお、本実施例において各ＳＱＵＩＤ
センサユニットは球面上に配置されており、以下、この
面を測定面という。また、測定面上における各ＳＱＵＩ
Ｄセンサユニットの配置位置を測定点という。Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of an embodiment of the biological activity current source estimation device according to the present invention. In the figure, reference numeral 10 is a magnetic shield room, and the bed 11 on which the subject M lies on the magnetic shield room 10 and the diagnosis target region of the subject M, for example, the brain, are provided in proximity to each other and are generated in the brain. Multi-channel SQU for non-invasive measurement of minute magnetic field by living body current source
The ID sensor 12 is provided. The multi-channel SQUID sensor 12 has a plurality of SQUID sensor units arranged in a refrigerant container called a dewar, and is immersed in a refrigerant such as liquid helium for accommodation. Each SQU
The ID sensor unit is composed of three SQUID sensors that respectively measure (vector measurement) orthogonal three-axis components of the magnetic field. The specific configuration of the SQUID sensor unit will be described later in detail. In this embodiment, each SQUID
The sensor unit is arranged on a spherical surface, and this surface is hereinafter referred to as a measurement surface. In addition, each SQUID on the measurement surface
The arrangement position of the D sensor unit is called a measurement point.
【００１３】マルチチャンネルＳＱＵＩＤセンサ１２で
検出された各測定点の磁界データはデータ変換ユニット
１３に与えられてデジタルデータに変換された後、デー
タ収集ユニット１４に集められる。刺激装置１５は、被
検体Ｍに電気的刺激（あるいは音、光刺激など）を与え
るためのものである。ポジショニングユニット１６は、
マルチチャンネルＳＱＵＩＤセンサ１２を基準とした３
次元座標系に対する被検体Ｍの位置関係を把握するため
の装置である。例えば、被検体Ｍの複数箇所に小コイル
を取り付け、これらの小コイルにポジショニングユニッ
ト１６から給電する。そして、各コイルから発生した磁
界をマルチチャンネルＳＱＵＩＤセンサ１２で検出する
ことにより、マルチチャンネルＳＱＵＩＤセンサ１２に
対する被検体Ｍの位置関係を把握する。The magnetic field data of each measurement point detected by the multi-channel SQUID sensor 12 is given to the data conversion unit 13 and converted into digital data, and then collected in the data collection unit 14. The stimulator 15 is for applying electrical stimulation (or sound, optical stimulation, etc.) to the subject M. The positioning unit 16 is
3 based on multi-channel SQUID sensor 12
This is a device for grasping the positional relationship of the subject M with respect to the dimensional coordinate system. For example, small coils are attached to a plurality of locations on the subject M, and the positioning unit 16 supplies power to these small coils. Then, the magnetic field generated from each coil is detected by the multi-channel SQUID sensor 12 to grasp the positional relationship of the subject M with respect to the multi-channel SQUID sensor 12.
【００１４】本実施例の要部であるデータ解析ユニット
１７は、データ収集ユニット１４に集められた磁界デー
タに基づいて、各測定点における垂直方向の磁界成分お
よび水平２方向の磁界成分を求める磁界成分算出部１８
と、各測定点における垂直方向の磁界強度および水平方
向の合成磁界強度に基づき、測定面上の多数の格子点に
おける垂直磁界成分および水平合成磁界成分をスプライ
ン補間などによって算出する補間処理部１９と、垂直磁
界成分の大きさの等しい格子点を順次連結することによ
って垂直磁界成分の等磁界線図を求める等磁界線図作成
部２０と、垂直磁界成分の等磁界線図に補間処理部１９
で求められた各格子点の水平合成磁界成分のベクトルの
矢印表示を重ね合わせる合成処理部２１などから構成さ
れている。The data analysis unit 17, which is the main part of this embodiment, calculates the magnetic field components in the vertical direction and the horizontal two-direction magnetic field component at each measurement point based on the magnetic field data collected in the data collection unit 14. Component calculator 18
And an interpolation processing unit 19 that calculates vertical magnetic field components and horizontal synthetic magnetic field components at a large number of grid points on the measurement surface by spline interpolation or the like based on the vertical magnetic field strength and the horizontal synthetic magnetic field strength at each measurement point. , An isomagnetic field map creation unit 20 that obtains an isomagnetic field map of the vertical magnetic field component by sequentially connecting grid points having the same magnitude of the perpendicular magnetic field component, and an interpolation processing unit 19 for the isomagnetic field map of the vertical magnetic field component.
It is composed of a synthesis processing unit 21 and the like for superimposing the arrow display of the vector of the horizontal synthesis magnetic field component of each lattice point obtained in step S1.
【００１５】そして、データ解析ユニット１７には、合
成処理部２１で重ね合わせ処理された等磁界線図を出力
する出力手段としての、等磁界線図を表示するカラーモ
ニタ２２と、それを印字出力するカラープリンタ２３と
が接続されている。In the data analysis unit 17, a color monitor 22 for displaying the isomagnetic field map as an output means for outputting the isomagnetic field map superposed by the synthesizing section 21, and a printout thereof. The color printer 23 is connected.
【００１６】次に図２，図３を参照してマルチチャンネ
ルＳＱＵＩＤセンサ１２を構成するＳＱＵＩＤセンサユ
ニットについて説明する。このＳＱＵＩＤセンサユニッ
トは３軸型グラジオメータとも呼ばれるもので、例えば
図２に示すように、フィルムＦ上にそれぞれ電気的に絶
縁分離して形成された３つのコイル対３１，３２，３３
を備える。例えば、コイル対３１は、三角関数で表され
る２つの導電パターン３１ａ，３１ｂの両端を直線の導
電パターンＡ，Ｂで接続したもので、導電パターン３１
ｂに接続端子３１ｃが形成されている。他のコイル対３
２，３３も同様の導電パターン３２ａ，３２ｂ，３３
ａ，３３ｂで構成されている。各コイル対３１，３２，
３３の導電パターンはそれぞれ横方向に（２／３）πａ
だけシフトして配置されている。ここで、符号ａは後述
するコイルボビンの半径である。Next, the SQUID sensor unit constituting the multi-channel SQUID sensor 12 will be described with reference to FIGS. This SQUID sensor unit is also called a triaxial gradiometer, and for example, as shown in FIG. 2, three coil pairs 31, 32, 33 formed on the film F are electrically insulated and separated.
Is provided. For example, the coil pair 31 is formed by connecting two ends of two conductive patterns 31a and 31b represented by a trigonometric function with linear conductive patterns A and B.
The connection terminal 31c is formed on b. Other coil pairs 3
2, 33 also have similar conductive patterns 32a, 32b, 33
a, 33b. Each coil pair 31, 32,
33 conductive patterns are (2/3) πa each in the lateral direction.
Only shifted and arranged. Here, the symbol a is the radius of the coil bobbin described later.
【００１７】３つのコイル対３１，３２，３３が形成さ
れたフィルムＦを、直線の導電パターンＡ，Ｂが近接す
るように、コイルボビンに巻き付け固定する。その状態
を図３に示す。これにより、例えばコイル対３１の導電
パターン３１ａは検出コイルを、導電パターン３１ｂは
補償コイルをそれぞれ形成し、各コイルは差動結合され
た状態になる。各コイル対３１，３２，３３の端子３１
ｃ，３２ｃ，３３ｃは図示しないＳＱＵＩＤ素子に接続
される。このようにして形成されたＳＱＵＩＤセンサユ
ニット３０が、図４に示すように、冷媒容器３４内の球
面上に配置される。The film F on which the three coil pairs 31, 32, 33 are formed is wound and fixed on the coil bobbin so that the linear conductive patterns A, B are close to each other. FIG. 3 shows this state. Thereby, for example, the conductive pattern 31a of the coil pair 31 forms a detection coil, the conductive pattern 31b forms a compensation coil, and the coils are differentially coupled. Terminal 31 of each coil pair 31, 32, 33
c, 32c and 33c are connected to a SQUID element (not shown). The SQUID sensor unit 30 thus formed is arranged on the spherical surface inside the refrigerant container 34, as shown in FIG.
【００１８】なお、磁界の３軸方向成分を検出するＳＱ
ＵＩＤセンサユニットは、上述のものに限らず、例えば
図５（ａ）に示すように、それぞれ差動結合されたコイ
ル対３５，３６，３７を立方体上にそれぞれ異なる方向
に巻き付け形成してもよく、あるいは、図５（ｂ）に示
すように、差動結合された平面コイル対３８，３９，４
０を立方体の直交する３面にそれぞれ貼り付け形成して
もよい。SQ for detecting the three-axis components of the magnetic field
The UID sensor unit is not limited to the above-described one, but as shown in FIG. 5A, for example, differentially coupled coil pairs 35, 36, and 37 may be formed on a cube by winding in different directions. Alternatively, as shown in FIG. 5B, differentially coupled planar coil pairs 38, 39, 4
0 may be formed by adhering to each of the three orthogonal surfaces of the cube.
【００１９】次に、本実施例装置による等磁界線図の作
成処理について説明する。マルチチャンネルＳＱＵＩＤ
センサ１２と被検体Ｍの位置関係を設定したのち、被検
体Ｍの診断対象領域内の生体活動電流源ｍによって生じ
た微小磁界（各測定点における３軸方向の磁界成分）を
マルチチャンネルＳＱＵＩＤセンサ１２内の各ＳＱＵＩ
Ｄセンサユニット３０によって計測し、得られた各測定
点の磁界データをデータ収集ユニット１４に収集する。Next, the process of creating an isomagnetic field map by the apparatus of this embodiment will be described. Multi-channel SQUID
After the positional relationship between the sensor 12 and the subject M is set, a micro magnetic field (a magnetic field component in three axial directions at each measurement point) generated by the biological activity current source m in the diagnostic target region of the subject M is used as a multi-channel SQUID sensor. Each SQUI in 12
The magnetic field data of each measurement point obtained by the measurement by the D sensor unit 30 is collected in the data collection unit 14.
【００２０】データ収集が終わると、磁界成分算出部１
８が各測定点における３軸方向の磁界成分、すなわち垂
直磁界成分と水平２方向の磁界成分とを求める。ここ
で、垂直磁界成分とは、測定面を構成する仮想の球体の
半径方向の磁界成分Ｂｒをいう（図１２参照）。また、
水平２方向の磁界成分とは、前記半径方向に垂直な（す
なわち、各測定点で測定面に接する）平面における直交
２方向の磁界成分Ｂθ，Ｂφをいう。なお、図３に示し
たＳＱＵＩＤセンサユニットの各コイル対３１，３２，
３３の各コイル軸芯は、磁界成分Ｂｒ，Ｂθ，Ｂφの各
方向に必ずしも一致しないので、この場合、各ＳＱＵＩ
Ｄセンサユニットで検出された独立した任意の３方向成
分から磁界成分Ｂｒ，Ｂθ，Ｂφを算出する。When the data collection is completed, the magnetic field component calculator 1
Reference numeral 8 determines the magnetic field components in the three axial directions at each measurement point, that is, the vertical magnetic field component and the horizontal two-direction magnetic field component. Here, the vertical magnetic field component refers to the magnetic field component Br in the radial direction of the virtual sphere forming the measurement surface (see FIG. 12). Also,
The horizontal two-direction magnetic field components mean magnetic field components Bθ and Bφ in two orthogonal directions on a plane perpendicular to the radial direction (that is, in contact with the measurement surface at each measurement point). In addition, each coil pair 31, 32 of the SQUID sensor unit shown in FIG.
Since each coil axis of 33 does not necessarily correspond to each direction of the magnetic field components Br, Bθ, Bφ, in this case, each SQUI
Magnetic field components Br, Bθ, and Bφ are calculated from the independent arbitrary three-direction components detected by the D sensor unit.
【００２１】各ＳＱＵＩＤセンサユニット３０が配置さ
れた測定点における垂直方向の磁界成分および水平２方
向の磁界成分が求められると、補間処理部１９が各測定
点の垂直・水平磁界成分に基づいて、測定面上に設定し
た多数の格子点上の垂直方向磁界成分および水平２方向
の合成磁界成分をスプライン補間などを使って算出す
る。When the vertical magnetic field component and the horizontal two-direction magnetic field component at the measurement point where each SQUID sensor unit 30 is arranged are obtained, the interpolation processing unit 19 determines the vertical and horizontal magnetic field components at each measurement point. Vertical magnetic field components on a large number of grid points set on the measurement surface and composite magnetic field components in two horizontal directions are calculated by using spline interpolation or the like.
【００２２】そして、等磁界線図作成部２０は、測定面
（球面）上の各格子点の垂直方向の磁界成分の強度分布
を適当な２次元平面に投影し、この２次元平面上の各格
子点において、磁界強度の等しい格子点を順次連結する
ことによって、垂直磁界成分の等磁界線図を作成する。
この等磁界線図を図６に例示する。Then, the isomagnetic field map drawing unit 20 projects the intensity distribution of the magnetic field component in the vertical direction of each lattice point on the measurement surface (spherical surface) onto an appropriate two-dimensional plane, and on each of the two-dimensional planes. At the lattice points, by sequentially connecting the lattice points having the same magnetic field strength, an isomagnetic field map of the vertical magnetic field component is created.
This isomagnetic field diagram is illustrated in FIG.
【００２３】この垂直磁界成分の等磁界線図のデータは
合成処理部２１に送られる。また、補間処理部１９で算
出された各格子点における水平２方向の合成磁界成分も
合成処理部２１に送られる。各格子点における水平２方
向の合成磁界成分の分布をベトクルの矢印表示で示した
模式図を図７に示す。合成処理部２１は、図６に示した
垂直磁界成分の等磁界線図と、図７に示した各格子点の
合成磁界成分のベトクルの矢印表示とを重ね合わせ処理
して、図８に示すような重ね合わせ等磁界線図を作成す
る。The data of the isomagnetic field map of the vertical magnetic field component is sent to the synthesis processing section 21. The combined magnetic field components in the two horizontal directions at each grid point calculated by the interpolation processing unit 19 are also sent to the combination processing unit 21. FIG. 7 is a schematic diagram showing the distribution of the composite magnetic field components in the two horizontal directions at each lattice point, as indicated by the arrows of the vectors. The synthesizing processing unit 21 superimposes the contour lines of the vertical magnetic field component shown in FIG. 6 and the arrow display of the vector of the synthetic magnetic field component of each lattice point shown in FIG. Create such a superposed magnetic field contour map.
【００２４】以上のようにして得られた重ね合わせ等磁
界線図は、必要に応じてカラーモニタ２２に表示された
り、あるいはカラープリンタ２３で印字出力されたりし
て、診断に供される。図８に示した重ね合わせの等磁界
線図から明らかなように、垂直磁界成分の等磁界線図の
上に、各格子点における水平２方向の合成磁界成分がベ
クトルの矢印表示で表されているので、電流源の個数や
位置などの総合的判断を容易に行なうことができる。ま
た、ノイズ等に起因して垂直磁界成分の等磁界線図上で
ピークと見えるような箇所があっても、水平成分の矢印
表示が全体としてその箇所に向かっていないような場合
には、その箇所のピークは本来の生体活動電流源によっ
て生じたものでないと判定できるので、電流源推定を的
確に行なうこともできる。The superposed magnetic field contour map obtained as described above is displayed on the color monitor 22 or printed out by the color printer 23 as needed for diagnosis. As is clear from the superimposed isomagnetic field diagram shown in FIG. 8, the horizontal two-direction composite magnetic field components at each lattice point are represented by vector arrows on the isomagnetic field diagram of the vertical magnetic field components. Therefore, it is possible to easily make a comprehensive judgment such as the number and position of the current sources. In addition, even if there is a peak that appears as a peak on the contour diagram of the vertical magnetic field component due to noise, etc. Since it can be determined that the peak at the location is not caused by the original biological activity current source, the current source can be accurately estimated.
【００２５】なお、上述の実施例では垂直磁界成分の等
磁界線図上に水平２方向の合成磁界成分のベクトルの矢
印表示を重ね合わせたが、この発明はこれに限定され
ず、水平２方向の合成磁界成分の等磁界線図上に各格子
点の垂直磁界成分に関連したベクトルの矢印表示を重ね
合わせてもよい。以下、具体的に説明する。In the above-described embodiment, the arrows of the vector of the combined magnetic field components in the two horizontal directions are superimposed on the isomagnetic field diagram of the vertical magnetic field component, but the present invention is not limited to this and the two horizontal directions. You may superimpose the arrow display of the vector relevant to the perpendicular magnetic field component of each lattice point on the isomagnetic field diagram of the composite magnetic field component of. Hereinafter, a specific description will be given.
【００２６】図１に示した磁界成分算出部１８で求めら
れた水平２方向の合成磁界成分Ｂθ，Ｂφから、その磁
界強度（大きさ）Ｂｈを求める。水平方向の磁界強度Ｂ
ｈは、次式から容易に求められる。 Ｂｈ＝√（Ｂθ2 ＋Ｂφ2)The magnetic field strength (magnitude) Bh is calculated from the horizontal two-direction combined magnetic field components Bθ and Bφ calculated by the magnetic field component calculation unit 18 shown in FIG. Horizontal magnetic field strength B
h can be easily obtained from the following equation. Bh = √ (Bθ 2 + Bφ 2 )
【００２７】そして、補間処理部１９で各格子点におけ
る水平方向の磁場強度をスプライン補間などで求める。
続いて、等磁界線図作成部２０で水平２方向の合成磁界
成分の等磁界線図を作成する。この等磁界線図の一例を
図９に示す。Then, the interpolation processing unit 19 obtains the magnetic field strength in the horizontal direction at each lattice point by spline interpolation or the like.
Then, the isomagnetic field map creation unit 20 creates isomagnetic field maps of the composite magnetic field components in the two horizontal directions. An example of this isomagnetic field diagram is shown in FIG.
【００２８】一方、磁界成分算出部１８で各測定点にお
ける垂直磁界成分Ｂｒの回転成分（すなわち、rot(Ｂ
ｒ) ベクトル）を求める。さらに、補間処理部１９にお
いて、各格子点のrot(Ｂｒ) ベクトルを補間演算によっ
て求める。求められたrot(Ｂｒ) ベクトルの分布図を図
１０に示す。On the other hand, in the magnetic field component calculation unit 18, the rotation component of the vertical magnetic field component Br at each measurement point (that is, rot (B
r) Find the vector). Further, the interpolation processing unit 19 obtains the rot (Br) vector of each lattice point by interpolation calculation. A distribution diagram of the obtained rot (Br) vector is shown in FIG.
【００２９】そして、合成処理部２１によって、水平磁
界成分の等磁界線図上に、垂直磁界成分のrot(Ｂｒ) ベ
クトルの分布を重ね合わせて、その重ね合わせ等磁界線
図をカラーモニタ２２やカラープリンタ２３から出力す
る。重ね合わされた等磁界線図を図１１に示す。Then, the composition processing unit 21 superimposes the distribution of the rot (Br) vector of the vertical magnetic field component on the isomagnetic field diagram of the horizontal magnetic field component, and the superimposed isomagnetic field diagram is displayed on the color monitor 22 or Output from the color printer 23. FIG. 11 shows the superimposed contour lines.
【００３０】[0030]
【発明の効果】以上の説明から明らかなように、この発
明によれば、垂直磁界成分の等磁界線図上に水平２方向
の合成磁界成分のベクトルの矢印表示を重ね合わせて出
力するか、あるいは、水平２方向の合成磁界成分の等磁
界線図上に垂直磁界成分に関連したベクトルの矢印表示
を重ね合わせて出力するようにしたので、何れにして
も、垂直磁界成分の分布と水平磁界成分の分布とを一つ
の等磁界線図上で確認することができる。したがって、
２つの等磁界線図を見比べる場合と比較して、生体活動
電流源の個数や位置などの総合的判断を容易かつ迅速に
行なうことができる。As is apparent from the above description, according to the present invention, the arrows of the vector of the combined magnetic field components in the two horizontal directions are superimposed and output on the contour lines of the vertical magnetic field components, or Alternatively, since the arrow display of the vector relating to the vertical magnetic field component is superimposed and output on the isomagnetic field map of the composite magnetic field components in the two horizontal directions, the distribution of the vertical magnetic field component and the horizontal magnetic field are in any case output. The distribution of the components can be confirmed on one contour plot. Therefore,
Compared with the case of comparing two isomagnetic field diagrams, it is possible to easily and quickly make a comprehensive determination of the number and position of the biological activity current sources.
【図１】この発明にかかる生体磁気計測装置一実施例の
概略構成を示すブロック図である。FIG. 1 is a block diagram showing a schematic configuration of an embodiment of a biomagnetism measuring device according to the present invention.
【図２】ＳＱＵＩＤセンサユニットの展開状態を示す図
である。FIG. 2 is a diagram showing a developed state of an SQUID sensor unit.
【図３】ＳＱＵＩＤセンサユニットの組立て状態を示す
図である。FIG. 3 is a view showing an assembled state of the SQUID sensor unit.
【図４】実施例装置で使用されるマルチチャンネルＳＱ
ＵＩＤセンサの概略構成図である。FIG. 4 is a multi-channel SQ used in the embodiment apparatus.
It is a schematic block diagram of a UID sensor.
【図５】ＳＱＵＩＤセンサユニットの変形例を示す斜視
図である。FIG. 5 is a perspective view showing a modified example of the SQUID sensor unit.
【図６】垂直磁界成分の等磁界線図である。FIG. 6 is an isomagnetic field diagram of a vertical magnetic field component.
【図７】水平２方向の合成磁界成分の分布図である。FIG. 7 is a distribution diagram of a composite magnetic field component in two horizontal directions.
【図８】重ね合わせ処理された等磁界線図である。FIG. 8 is an isomagnetic field diagram after superposition processing.
【図９】変形例に係る水平２方向の合成磁界成分の等磁
界線図である。FIG. 9 is an isomagnetic field diagram of a composite magnetic field component in two horizontal directions according to a modification.
【図１０】変形例に係る垂直磁界成分の回転ベクトル成
分の分布図である。FIG. 10 is a distribution diagram of rotation vector components of a vertical magnetic field component according to a modification.
【図１１】変形例に係る重ね合わせ処理された等磁界線
図である。FIG. 11 is an isomagnetic field line diagram subjected to superposition processing according to a modification.
【図１２】従来例に係るＳＱＵＩＤセンサの説明図であ
る。FIG. 12 is an explanatory diagram of a SQUID sensor according to a conventional example.
【図１３】従来例に係るマルチチャンネルＳＱＵＩＤセ
ンサの説明図である。FIG. 13 is an explanatory diagram of a multi-channel SQUID sensor according to a conventional example.
【図１４】従来例に係る垂直磁界成分の等磁界線図であ
る。FIG. 14 is an isomagnetic field diagram of a vertical magnetic field component according to a conventional example.
【図１５】先に提案された装置で得られる水平磁界成分
の等磁界線図である。FIG. 15 is an isomagnetic field diagram of a horizontal magnetic field component obtained by the previously proposed device.
１２…マルチチャンネルＳＱＵＩＤセンサ １８…磁界成分算出部 １９…補間処理部 ２０…等磁界線図作成部 ２１…合成処理部 ２２…カラーモニタ ２３…カラープリンタ 12 ... Multi-channel SQUID sensor 18 ... Magnetic field component calculation unit 19 ... Interpolation processing unit 20 ... Isomagnetic field map creation unit 21 ... Synthesis processing unit 22 ... Color monitor 23 ... Color printer
Claims (1)
（測定点）に配備され、前記診断対象領域内の生体活動
電流源による微小磁界の直交３軸成分を各測定点で計測
する複数個の磁気センサと、前記各磁気センサで計測さ
れた各測定点の磁界の直交３軸成分から各測定点におけ
る垂直方向の磁界成分および水平２方向の磁界成分を求
める磁界成分算出手段と、前記各測定点における垂直方
向の磁界成分および水平２方向の合成磁界成分に基づ
き、各磁気センサが置かれた測定面上の多数の格子点に
おける垂直磁界成分および水平合成磁界成分を算出する
補間処理手段と、磁界成分の大きさの等しい格子点を順
次連結することによって垂直磁界成分または水平合成磁
界成分のいずれか一方の等磁界線図を求める等磁界線図
作成手段と、垂直磁界成分の等磁界線図を求めた場合に
は、この等磁界線図に各格子点の水平合成磁界成分のベ
トクルの矢印表示を重ね合わせる一方、水平合成磁界成
分の等磁界線図を求めた場合には、この等磁界線図に各
格子点の垂直磁界成分に関連したベトクルの矢印表示を
重ね合わせる合成処理手段と、前記合成処理された等磁
界線図を出力する出力手段と、を備えたことを特徴とす
る生体磁気計測装置。1. A plurality of devices arranged at respective positions (measurement points) close to a diagnosis target region of a subject and measuring orthogonal three-axis components of a minute magnetic field generated by a biological activity current source in the diagnosis target region at each measurement point. Magnetic field component calculation means for obtaining a magnetic field component in the vertical direction and a magnetic field component in two horizontal directions at each measurement point from the three orthogonal magnetic field components of the magnetic field at each measurement point measured by each magnetic sensor; Interpolation processing means for calculating vertical magnetic field components and horizontal composite magnetic field components at a large number of grid points on the measurement surface on which each magnetic sensor is placed based on the vertical magnetic field component and horizontal two-direction composite magnetic field component at each measurement point. And an isomagnetic field map creating means for obtaining an isomagnetic field map of either a vertical magnetic field component or a horizontal composite magnetic field component by sequentially connecting grid points having the same magnetic field component magnitude, and a vertical magnetic field. When the isomagnetic field map of the component is obtained, the contour arrow of the horizontal synthetic magnetic field component of each lattice point is superimposed on this isomagnetic field diagram, while the isomagnetic field diagram of the horizontal synthetic magnetic field component is obtained. Is provided with combining processing means for superposing the arrow mark of the vector related to the vertical magnetic field component of each lattice point on this isomagnetic field diagram, and output means for outputting the combined isomagnetic field diagram. A biomagnetism measuring device characterized by the above.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34760795A JP3407520B2 (en) | 1995-12-14 | 1995-12-14 | Biomagnetic measurement device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34760795A JP3407520B2 (en) | 1995-12-14 | 1995-12-14 | Biomagnetic measurement device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH09164123A true JPH09164123A (en) | 1997-06-24 |
| JP3407520B2 JP3407520B2 (en) | 2003-05-19 |
Family
ID=18391369
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP34760795A Expired - Fee Related JP3407520B2 (en) | 1995-12-14 | 1995-12-14 | Biomagnetic measurement device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3407520B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004110269A1 (en) * | 2003-06-11 | 2004-12-23 | Japan Science And Technology Agency | Sensor for magnetoencephalography meter and supermultichannel magnetoencephalography meter system using the same |
| WO2009087780A1 (en) * | 2008-01-10 | 2009-07-16 | The University Of Tokushima | Jaw movement measuring device and method for manufacturing sensor coil for use in the same |
| US7680524B2 (en) | 2001-10-23 | 2010-03-16 | Olympus Corporation | Magnetic fluid detection method and magnetic fluid detection apparatus |
| JP2021177159A (en) * | 2020-05-08 | 2021-11-11 | 旭化成エレクトロニクス株式会社 | Magnetic field measuring device, magnetic field measuring method, and magnetic field measuring program |
-
1995
- 1995-12-14 JP JP34760795A patent/JP3407520B2/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7680524B2 (en) | 2001-10-23 | 2010-03-16 | Olympus Corporation | Magnetic fluid detection method and magnetic fluid detection apparatus |
| WO2004110269A1 (en) * | 2003-06-11 | 2004-12-23 | Japan Science And Technology Agency | Sensor for magnetoencephalography meter and supermultichannel magnetoencephalography meter system using the same |
| US7672707B2 (en) | 2003-06-11 | 2010-03-02 | Japan Science And Technology Agency | Sensor for magnetoencephalography meter and supermultichannel magnetoencephalography meter system using the same |
| WO2009087780A1 (en) * | 2008-01-10 | 2009-07-16 | The University Of Tokushima | Jaw movement measuring device and method for manufacturing sensor coil for use in the same |
| JP4665051B2 (en) * | 2008-01-10 | 2011-04-06 | 国立大学法人徳島大学 | Jaw movement measuring device and sensor coil manufacturing method used therefor |
| JP2021177159A (en) * | 2020-05-08 | 2021-11-11 | 旭化成エレクトロニクス株式会社 | Magnetic field measuring device, magnetic field measuring method, and magnetic field measuring program |
| US12082915B2 (en) | 2020-05-08 | 2024-09-10 | Asahi Kasei Microdevices Corporation | Magnetic field measurement device, magnetic field measurement method, and recording medium having magnetic field measurement program recorded thereon |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3407520B2 (en) | 2003-05-19 |
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