JPH0678893A - Magnetic resonance imaging device - Google Patents
Magnetic resonance imaging deviceInfo
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- JPH0678893A JPH0678893A JP4237003A JP23700392A JPH0678893A JP H0678893 A JPH0678893 A JP H0678893A JP 4237003 A JP4237003 A JP 4237003A JP 23700392 A JP23700392 A JP 23700392A JP H0678893 A JPH0678893 A JP H0678893A
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- yokes
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- yoke
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、磁気共鳴イメージング
装置に係り、特に、被検体の挿入される計測空間内に静
磁場を形成する磁気回路の改良に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic resonance imaging apparatus, and more particularly to improvement of a magnetic circuit for forming a static magnetic field in a measurement space into which a subject is inserted.
【０００２】[0002]
【従来の技術】磁気共鳴イメージング装置は、いわゆる
核磁気共鳴（ＮＭＲ）現象を利用して被検体の検査部位
における断層像を得る装置である。2. Description of the Related Art A magnetic resonance imaging apparatus is an apparatus for obtaining a tomographic image at an examination site of a subject by utilizing a so-called nuclear magnetic resonance (NMR) phenomenon.
【０００３】そして、被検体の検査部位に該ＮＭＲ現象
を生じさせる一手段として、該被検体の挿入される計測
空間内に静磁場を形成する磁気回路を備えている。A magnetic circuit for forming a static magnetic field in the measurement space into which the subject is inserted is provided as a means for producing the NMR phenomenon at the examination site of the subject.
【０００４】この磁気回路としては、従来次のようにし
て構成されていた。This magnetic circuit has conventionally been constructed as follows.
【０００５】たとえば、図９に示すように、計測空間９
１を間にして互に対向配置された第１継鉄９２Ａ、９２
Ｂがあり、これら各第１継鉄９２Ａ、９２Ｂは、図中矢
印α方向から挿入される被検体の両脇に相当する部分
（第１継鉄の各角部）にて第２継鉄９３Ａ、９３Ｂ、９
３Ｃ、９３Ｄによって支持され、前記第１継鉄９２Ａ、
９２Ｂの前記計測空間９１側の面のほぼ中央部にそれぞ
れ円板状の永久磁石９４Ａ（図示されてない）、９４Ｂ
が固定されたものとなっている。For example, as shown in FIG.
1st yokes 92A, 92 which are arranged to face each other with 1 in between
B, and each of these first yokes 92A, 92B is a second yoke 93A at a portion (each corner of the first yoke) corresponding to both sides of the subject to be inserted from the direction of the arrow α in the figure. , 93B, 9
3C, 93D, the first yoke 92A,
Disk-shaped permanent magnets 94A (not shown) and 94B are provided at substantially the center of the surface of the measurement space 91 side of 92B.
Has been fixed.
【０００６】[0006]
【発明が解決しようとする課題】しかしながら、このよ
うに構成された磁気回路は、被検体の計測空間９１への
挿入口が、第１継鉄９２Ａ、９２Ｂと前方に位置付けら
れた第２継鉄９３Ａ、９３Ｂによって決定され、比較的
間口の狭いものとなっていた。However, in the magnetic circuit configured as described above, the insertion port of the object to be measured into the measurement space 91 is the second yoke with the first yokes 92A and 92B positioned in front. It was determined by 93A and 93B and had a relatively narrow frontage.
【０００７】このため、被検体が該計測空間９１に挿入
された場合に、いわゆる圧迫感を生じさせることは免れ
ず、不安感を与える原因になっていた。Therefore, when the subject is inserted into the measurement space 91, it is unavoidable that a so-called pressure feeling is generated, which causes anxiety.
【０００８】また、近年では、被検体における特殊な部
位を診断することが往々にしてあり、この場合、計測空
間９１への挿入口の間口が狭いと、被検体における特殊
な部位を自由に診断することが困難になるという問題が
残されていた。Further, in recent years, it is often the case that a special part of the subject is diagnosed. In this case, if the frontage of the insertion opening into the measurement space 91 is narrow, the special part of the subject can be freely diagnosed. There was a problem that it would be difficult to do.
【０００９】それ故、本発明はこのような事情に基づい
てなされたものであり、その目的とするところのもの
は、被検体に圧迫感を与えず、しかも被検体における特
殊な部位を自由に診断することができる磁気共鳴イメー
ジング装置を提供することにある。Therefore, the present invention has been made under such circumstances, and the object of the present invention is not to give a feeling of pressure to a subject, and to freely set a special portion of the subject. An object of the present invention is to provide a magnetic resonance imaging apparatus that can make a diagnosis.
【００１０】[0010]
【課題を解決するための手段】このような目的を達成す
るために、本発明による磁気共鳴イメージング装置は、
基本的には、被検体の挿入される計測空間内に静磁場を
形成する磁気回路を備え、この磁気回路は、前記計測空
間を間にして互に対向配置された第１継続と、これら各
継鉄を挿入される被検体の両脇に相当する部分にて支持
する第２継鉄と、前記第１継鉄の前記計測空間側の面の
ほぼ中央部にそれぞれ固定された永久磁石とからなる磁
気共鳴イメージング装置において、前記第２継鉄は、そ
の該被検体の挿入方向における幅が、前記永久磁石の同
方向における幅よりも小さくなっているとともに、前記
永久磁石の中心を通りかつ該被検体挿入方向に直交する
仮想線上あるいはそれよりも後方に位置付けられ、前記
第１継鉄は、その該被検体の挿入方向における幅が、前
記第２継鉄を支持する箇所において小さくなっているこ
とを特徴とするものである。In order to achieve such an object, a magnetic resonance imaging apparatus according to the present invention comprises:
Basically, a magnetic circuit for forming a static magnetic field is provided in the measurement space into which the subject is inserted, and the magnetic circuit includes a first continuation arranged to face each other with the measurement space in between, and each of these first continuations. From the second yoke supporting the yoke at portions corresponding to both sides of the subject to be inserted, and the permanent magnets fixed respectively to approximately the central portion of the surface on the measurement space side of the first yoke. In the magnetic resonance imaging apparatus, the second yoke has a width in the insertion direction of the subject smaller than a width of the permanent magnet in the same direction and passes through the center of the permanent magnet. The first yoke is positioned on or behind the imaginary line orthogonal to the subject insertion direction, and the width of the first yoke in the insertion direction of the subject is small at the portion supporting the second yoke. It is also characterized by It is.
【００１１】[0011]
【作用】このように構成した磁気共鳴イメージング装置
は、磁気回路における第２継鉄において、その被検体挿
入方向における幅を小さくし、かつ永久磁石の中心を通
りかつ被検体挿入方向に直行する仮想線上あるいはそれ
よりも後方に位置付けている。そして、第１継鉄は、そ
の被検体挿入方向における幅を前記第２継鉄を支持する
箇所において小さくしている。In the magnetic resonance imaging apparatus configured as described above, in the second yoke in the magnetic circuit, the width of the second yoke in the direction of insertion of the subject is reduced, and it passes through the center of the permanent magnet and goes straight in the direction of insertion of the subject. It is positioned on or behind the line. The width of the first yoke in the direction in which the subject is inserted is reduced at the location supporting the second yoke.
【００１２】このため、計測空間への挿入口は、その両
脇側が中央部に比べてひっこんだ形状とすることができ
る。このことから該挿入口の間口が実質的に大きくな
り、計測空間に挿入された被検体に圧迫感を生じさせる
ようなことはなくなる。For this reason, the insertion opening into the measurement space can have a shape in which both sides of the insertion opening are recessed as compared with the central portion. As a result, the frontage of the insertion port becomes substantially large, and the subject inserted into the measurement space does not feel a sense of pressure.
【００１３】また、計測空間の挿入口が両脇側において
やや側面方向に大きくなるような形状となることから、
該側面方向からも被検体を挿入することができ、したが
って、被検体における特殊な部位を自由に診断すること
ができるようになる。Further, since the insertion port of the measurement space is shaped to be slightly larger in the lateral direction on both sides,
The subject can be inserted also from the side direction, so that a special site in the subject can be freely diagnosed.
【００１４】[0014]
【実施例】図１は、本発明による磁気共鳴イメージング
装置に具備される磁気回路の一実施例を示す斜視構成図
である。1 is a perspective view showing the configuration of an embodiment of a magnetic circuit provided in a magnetic resonance imaging apparatus according to the present invention.
【００１５】同図において、該磁気回路１０は、図中、
矢印α方向から図示しない被検体が挿入する計測空間１
１を有する。そして、該計測空間１１を間にして互に対
向配置される第１継鉄１２Ａ、１２Ｂと、これら各第１
継鉄１２Ａ、１２Ｂを挿入される被検体の両脇に相当す
る部分にて支持する第２継鉄１３Ａ、１３Ｂと、前記第
１継鉄１２Ａ、１２Ｂの前記計測空間１１側の面のほぼ
中央部にそれぞれ固定された永久磁石１４Ａ（図示され
ていない）、１４Ｂ、とからなっている。In the figure, the magnetic circuit 10 is
Measurement space 1 inserted by a subject (not shown) from the direction of arrow α
Has 1. Then, the first yokes 12A and 12B arranged to face each other with the measurement space 11 in between, and the first yokes 12A and 12B.
Second yokes 13A, 13B supporting the yokes 12A, 12B at portions corresponding to both sides of the subject to be inserted, and substantially the center of the surface of the first yokes 12A, 12B on the side of the measurement space 11 The permanent magnets 14A (not shown) and 14B fixed to the respective parts.
【００１６】図２は、図１のII−II線における断面を示
す図で、しかも計測空間１１を横切る磁路を示してい
る。同図において、対向配置される永久磁石１４Ａ、１
４Ｂのうち一方の永久磁石１４Ｂにて発生する磁束は、
磁極片１５Ｂ、計測空間１１を通過し、磁極片１５Ａ、
永久磁石１４Ａ、第１継鉄１２Ａを通り、さらに第２継
鉄１３Ａ、１３Ｂ、第１継鉄１２Ｂを通って、永久磁石
１４Ｂに戻る閉ループを形成する磁気回路を構成するよ
うになっている。FIG. 2 is a view showing a cross section taken along the line II-II of FIG. 1, and shows a magnetic path crossing the measurement space 11. In the figure, the permanent magnets 14A and 1 are arranged to face each other.
The magnetic flux generated by one of the permanent magnets 14B of 4B is
After passing through the pole piece 15B and the measurement space 11, the pole piece 15A,
A magnetic circuit that forms a closed loop that passes through the permanent magnet 14A and the first yoke 12A, and further through the second yokes 13A and 13B and the first yoke 12B and returns to the permanent magnet 14B is configured.
【００１７】以下、前記第１継鉄１２Ａ、１２Ｂ、第２
継鉄１３Ａ、１３Ｂ、永久磁石１４Ａ、１４Ｂ等につい
てさらに詳述する。Hereinafter, the first yoke 12A, 12B, the second
The yokes 13A and 13B, the permanent magnets 14A and 14B, etc. will be described in more detail.
【００１８】第１継鉄１２Ａ、１２Ｂ それぞれの第１継鉄１２Ａ、１２Ｂは、その平面形状
が、ほぼ長方形の各角部が切りかかれた形状をなしてい
る。そして、各第１継鉄１２Ａ、１２Ｂは前記計測空間
１１を間にして互に対向配置され、それら各長軸方向は
被検体の挿入方向（図中α方向）に直交するように位置
付けられている。The first yoke 12A, 12B each of the first yoke 12A, 12B has a plane shape, has a shape that substantially each corner of the rectangle is Kirikakare. The first yokes 12A and 12B are arranged to face each other with the measurement space 11 in between, and the long axis directions of the first yokes 12A and 12B are positioned so as to be orthogonal to the insertion direction (α direction in the drawing) of the subject. There is.
【００１９】これにより、被検体の挿入方向αにおける
幅が、挿入される被検体の両脇において小さくなるよう
になっている。As a result, the width of the subject in the insertion direction α is reduced on both sides of the subject to be inserted.
【００２０】第２継鉄１３Ａ、１３Ｂ 互に対向配置された第１継鉄１２Ａ、１２Ｂを相互的に
支持するように、挿入される被検体の両脇の部分におい
て第２継鉄１３Ａ、１３Ｂが配置されている。 Second yokes 13A, 13B The second yokes 13A, 13B are provided on both sides of the subject to be inserted so as to mutually support the first yokes 12A, 12B arranged to face each other. Are arranged.
【００２１】この第２継鉄１３Ａ、１３Ｂは、その該被
検体の挿入方向αにおける幅が、後述する永久磁石１４
の同方向における幅よりも小さく構成されている。The widths of the second yokes 13A and 13B in the insertion direction α of the subject are such that the permanent magnets 14 to be described later are provided.
Is smaller than the width in the same direction.
【００２２】すなわち、前記第１継鉄１２Ａ、１２Ｂの
長軸方向の端部、換言すれば、挿入される被検体の両脇
における該被検体の挿入方向αにおける幅が小さく形成
された部分において、前記第２継鉄１３Ａ、１３Ｂが支
持されていることになる。That is, at the ends of the first yokes 12A and 12B in the long axis direction, in other words, at the portions formed on both sides of the subject to be inserted, the width of which is small in the inserting direction α of the subject. Thus, the second yokes 13A and 13B are supported.
【００２３】そして、第２継鉄１３Ａ、１３Ｂは、永久
磁石１４の中心を通りかつ該被検体挿入方向αに直交す
る仮想線上に位置付けられることになる。The second yokes 13A and 13B are positioned on an imaginary line passing through the center of the permanent magnet 14 and orthogonal to the subject insertion direction α.
【００２４】永久磁石１４Ａ（図示されていない）、１４Ｂ 永久磁石１４Ａ、１４Ｂは、それぞれ、円板状からな
り、前記第１継鉄１２Ａ、１２Ｂの計測空間１１側の面
に固定されている。The permanent magnets 14A (not shown) and 14B are made of discs, and are fixed to the surfaces of the first yokes 12A and 12B on the measurement space 11 side.
【００２５】この永久磁石１４Ａ、１４Ｂのそれぞれの
直径は等しく、前記第１継鉄１２Ａ、１２Ｂにはみ出す
ことなく充分大きいものとなっている。The diameters of the permanent magnets 14A and 14B are equal, and they are sufficiently large without protruding to the first yokes 12A and 12B.
【００２６】なお、ここで、図３を用いて、第１継鉄１
２Ａ、永久磁石１４Ａ、第２継鉄１３Ａ、１３Ｂの断面
のそれぞれの大きさについて説明する。同図において、
第２継鉄１３Ａ、１３Ｂの挿入方向αの幅Ｌ1は、第１
継鉄１２Ａの同方向の幅（永久磁石１４Ａの直径にほぼ
等しい）Ｌ2の略５０％となっている。そして、第２継
鉄１３Ａ、１３Ｂの挿入方向αと直交する幅Ｔをとり、
Ｔ×Ｌ1×２（２を乗算しているのは２本あるため）で
決定される面積を従来と同程度として磁気特性を従来と
同程度としているものである。このために、第１継鉄１
２Ａの挿入方向αと直交する幅Ｌ3が従来よりも大きく
なる場合があるが、特に、このことによって弊害がもた
らすことになるものではない。Here, referring to FIG. 3, the first yoke 1
The respective sizes of the cross sections of 2A, the permanent magnet 14A, and the second yokes 13A and 13B will be described. In the figure,
The width L 1 of the second yoke 13A, 13B in the insertion direction α is
The width of the yoke 12A in the same direction (approximately equal to the diameter of the permanent magnet 14A) L 2 is approximately 50%. Then, taking a width T orthogonal to the insertion direction α of the second yoke 13A, 13B,
The area determined by T × L 1 × 2 (because there are two that are multiplied by 2) is about the same as the conventional one, and the magnetic characteristics are about the same as the conventional one. For this purpose, the first yoke 1
The width L 3 orthogonal to the insertion direction α of 2A may become larger than in the conventional case, but this does not particularly cause any adverse effect.
【００２７】なお、各永久磁石１４Ａ、１４Ｂの計測空
間１１側の面には、それぞれ磁極片１５Ａ（図示されて
いない）、１５Ｂが配置され、また前記計測空間に傾斜
磁場を形成するための傾斜磁場コイル１６Ａ（図示され
ていない）、１６Ｂが配置されている。Magnetic pole pieces 15A (not shown) and 15B are arranged on the surfaces of the permanent magnets 14A and 14B on the measurement space 11 side, respectively, and a gradient for forming a gradient magnetic field in the measurement space. Magnetic field coils 16A (not shown) and 16B are arranged.
【００２８】なお、図４において、この磁気回路１０を
内包する外囲器４０を示しており、この外囲器４０にお
ける計測空間への挿入口４１は、該磁気回路１０のそれ
に応じて形成され、やはり挿入される被検体の両脇部４
１Ａ、４１Ｂにおいて中央部に比べて後方にひっこんだ
形状とすることができ、このことから該挿入口の間口を
従来と比べて実質的に大きくすることができる。なお、
図４には該挿入口４１の前方に被検体を載置するための
ベッド４２が配置されている。FIG. 4 shows an envelope 40 that encloses the magnetic circuit 10. An insertion port 41 in the measurement space of the envelope 40 is formed in accordance with the magnetic circuit 10. , Both sides 4 of the subject to be inserted
1A and 41B can have a shape that is recessed rearward compared to the central portion, which makes it possible to make the frontage of the insertion opening substantially larger than in the conventional case. In addition,
In FIG. 4, a bed 42 for placing a subject is arranged in front of the insertion port 41.
【００２９】上述した実施例による磁気回路１０によれ
ば、その第２継鉄１３Ａ、１３Ｂにおいて、その被検体
挿入方向αにおける幅を小さくし、かつ永久磁石１４
Ａ、１４Ｂの中心を通りかつ被検体挿入方向αに直行す
る仮想線上に位置づけている。そして、第１継鉄１２
Ａ、１２Ｂは、その被検体挿入方向αにおける幅を前記
第２継鉄１３Ａ、１３Ｂを支持する箇所において小さく
している。According to the magnetic circuit 10 according to the above-described embodiment, the width of the second yoke 13A, 13B in the subject insertion direction α is reduced and the permanent magnet 14 is used.
It is positioned on a virtual line that passes through the centers of A and 14B and is orthogonal to the subject insertion direction α. And the 1st yoke 12
The widths of A and 12B in the subject insertion direction α are reduced at the portions supporting the second yokes 13A and 13B.
【００３０】このため、計測空間１１への挿入口は、そ
の両脇側が中央部に比べてひっこんだ形状とすることが
できる。このことから該挿入口の間口が実質的に大きく
なり、計測空間１１に挿入された被検体に圧迫感を生じ
させるようなことはなくなる。For this reason, the insertion opening into the measurement space 11 can be formed so that both sides thereof are recessed as compared with the central portion. As a result, the frontage of the insertion port becomes substantially large, and the subject inserted into the measurement space 11 does not feel a sense of pressure.
【００３１】また、計測空間１１の挿入口が両脇側にお
いてやや側面方向に大きくなるような形状となることか
ら、該側面方向からも被検体を挿入することができ、し
たがって、被検体における特殊な部位を自由に診断する
ことができるようになる。Further, since the insertion opening of the measurement space 11 has a shape that is slightly enlarged in the lateral direction on both sides, the object can be inserted also in the lateral direction, and therefore the special object in the object can be inserted. It will be possible to freely diagnose various parts.
【００３２】なお、上述した第１継鉄１２Ａ、１２Ｂと
第２継鉄１３Ａ、１３Ｂのそれぞれの形状は、図１に示
したものに限定されず、図５ないし図８に示すように種
々の変形をもたらすことができることはいうまでもな
い。The shapes of the first yokes 12A and 12B and the second yokes 13A and 13B described above are not limited to those shown in FIG. 1, and various shapes are shown in FIGS. 5 to 8. It goes without saying that deformation can be brought about.
【００３３】上述した各実施例では、第１継鉄１２Ａ、
１２Ｂの平面形状は、ほぼ八角形としたものであるが、
必ずしもこれに限定されるものではなく、それぞれの角
部を削り滑らかな弧状となるように形成するようにして
もよいことはいうまでもない。要は、その該被検体の挿
入方向αにおける幅が、第２継鉄を支持する箇所におい
て小さくなっていればよい。In each of the above-mentioned embodiments, the first yoke 12A,
The plane shape of 12B is almost octagonal,
Of course, the present invention is not limited to this, and it goes without saying that each corner may be shaved to form a smooth arc shape. The point is that the width of the subject in the insertion direction α should be small at the portion supporting the second yoke.
【００３４】また、上述した実施例では、第２継鉄１３
Ａ、１３Ｂは、永久磁石１４Ａ、１４Ｂの中心を通りか
つ被検体挿入方向αに直行する仮想線上に位置づけるよ
うにしたものである。しかし、これに限定されることは
なく、該仮想線の後方に位置づけるようにしてもよいこ
とはいうまでもない。この場合においても被検体の計測
空間１１への挿入口の間口を充分大きくとれるからであ
る。In the above-mentioned embodiment, the second yoke 13 is used.
A and 13B are positioned on an imaginary line that passes through the centers of the permanent magnets 14A and 14B and is orthogonal to the subject insertion direction α. However, the present invention is not limited to this, and it goes without saying that it may be positioned behind the virtual line. Even in this case, the frontage of the insertion opening of the subject into the measurement space 11 can be made sufficiently large.
【００３５】[0035]
【発明の効果】以上説明したことから明らかなように、
本発明による磁気共鳴イメージング装置によれば、被検
体に圧迫感を与えず、しかも被検体における特殊な部位
を自由に診断することができるようになる。As is apparent from the above description,
According to the magnetic resonance imaging apparatus of the present invention, it is possible to freely diagnose a specific part of a subject without giving a sense of pressure to the subject.
【図１】本発明による磁気共鳴イメージング装置に具備
される磁気回路の一実施例を示す斜視構成図である。FIG. 1 is a perspective configuration diagram showing an embodiment of a magnetic circuit provided in a magnetic resonance imaging apparatus according to the present invention.
【図２】図１のII−II線における断面図で、かつ計測空
間を横切る磁路を示した説明図である。2 is a cross-sectional view taken along line II-II in FIG. 1 and is an explanatory view showing a magnetic path that crosses a measurement space.
【図３】図１に示す磁気回路における第１継鉄、第２継
鉄、永久磁石のそれぞれの大きさを説明するための説明
図である。FIG. 3 is an explanatory diagram for explaining respective sizes of a first yoke, a second yoke, and a permanent magnet in the magnetic circuit shown in FIG. 1.
【図４】本発明による磁気共鳴イメージング装置に具備
される磁気回路を内包する外囲器の一実施例を示す斜視
構成図である。FIG. 4 is a perspective configuration view showing an embodiment of an envelope including a magnetic circuit provided in the magnetic resonance imaging apparatus according to the present invention.
【図５】本発明による磁気共鳴イメージング装置に具備
される磁気回路の他の実施例を示す平面構成図である。FIG. 5 is a plan configuration diagram showing another embodiment of the magnetic circuit provided in the magnetic resonance imaging apparatus according to the present invention.
【図６】本発明による磁気共鳴イメージング装置に具備
される磁気回路の他の実施例を示す平面構成図である。FIG. 6 is a plan view showing another embodiment of the magnetic circuit provided in the magnetic resonance imaging apparatus according to the present invention.
【図７】本発明による磁気共鳴イメージング装置に具備
される磁気回路の他の実施例を示す平面構成図である。FIG. 7 is a plan configuration diagram showing another embodiment of the magnetic circuit provided in the magnetic resonance imaging apparatus according to the present invention.
【図８】本発明による磁気共鳴イメージング装置に具備
される磁気回路の他の実施例を示す平面構成図である。FIG. 8 is a plan view showing another embodiment of the magnetic circuit provided in the magnetic resonance imaging apparatus according to the present invention.
【図９】従来の磁気共鳴イメージング装置に具備される
磁気回路の一例を示す斜視構成図である。FIG. 9 is a perspective configuration diagram showing an example of a magnetic circuit provided in a conventional magnetic resonance imaging apparatus.
１１ 計測空間 １２ 第１継鉄 １３ 第２継鉄 １４ 永久磁石 11 Measuring Space 12 First Yoke 13 Second Yoke 14 Permanent Magnet
Claims (1)
を形成する磁場回路を備え、この磁場回路は、前記計測
空間を間にして互に対向配置された第１継鉄と、これら
各継鉄を挿入される被検体の両脇に相当する部分にて支
持する第２継鉄と、前記第１継鉄の前記計測空間側の面
のほぼ中央部にそれぞれ固定された永久磁石とからなる
磁気共鳴イメージング装置において、前記第２継鉄は、
その該被検体の挿入方向における幅が、前記永久磁石の
同方向における幅よりも小さくなっているとともに、前
記永久磁石の中心を通りかつ該被検体挿入方向に直交す
る仮想線上あるいはそれよりも後方に位置付けられ、前
記第１継鉄は、その該被検体の挿入方向における幅が、
前記第２継鉄を支持する箇所において小さくなっている
ことを特徴とする磁気共鳴イメージング装置。1. A magnetic field circuit for forming a static magnetic field in a measurement space in which a subject is inserted, the magnetic field circuit including first yokes arranged to face each other with the measurement space therebetween. A second yoke supporting each yoke at portions corresponding to both sides of the subject to be inserted, and a permanent magnet fixed to substantially the center of the surface of the first yoke on the side of the measurement space. In the magnetic resonance imaging apparatus including the second yoke,
The width of the subject in the insertion direction is smaller than the width of the permanent magnet in the same direction, and the virtual line passes through the center of the permanent magnet and is orthogonal to the subject insertion direction or behind it. The first yoke has a width in the insertion direction of the subject,
A magnetic resonance imaging apparatus characterized in that it is small in a portion supporting the second yoke.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4237003A JP2759185B2 (en) | 1992-09-04 | 1992-09-04 | Magnetic resonance imaging equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4237003A JP2759185B2 (en) | 1992-09-04 | 1992-09-04 | Magnetic resonance imaging equipment |
Related Child Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP09317723A Division JP3098214B2 (en) | 1997-11-04 | 1997-11-04 | Magnetic resonance imaging equipment |
| JP09317722A Division JP3080603B2 (en) | 1997-11-04 | 1997-11-04 | Static magnetic field generator for MRI equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0678893A true JPH0678893A (en) | 1994-03-22 |
| JP2759185B2 JP2759185B2 (en) | 1998-05-28 |
Family
ID=17008949
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4237003A Expired - Fee Related JP2759185B2 (en) | 1992-09-04 | 1992-09-04 | Magnetic resonance imaging equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2759185B2 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0691548A1 (en) | 1994-07-08 | 1996-01-10 | Sumitomo Special Metals Company Limited | Magnetic field generating device for use in MRI |
| JPH08140958A (en) * | 1994-11-25 | 1996-06-04 | Hitachi Medical Corp | Magnetic resonance imaging apparatus |
| EP0760484A2 (en) * | 1995-08-28 | 1997-03-05 | Shin-Etsu Chemical Co., Ltd. | Opposed magnet-type magnetic circuit assembly with permanent magnets |
| JPH09190913A (en) * | 1996-01-10 | 1997-07-22 | Hitachi Medical Corp | Superconducting magnet device and magnetic resonance imaging apparatus using this device |
| JPH1057345A (en) * | 1997-07-11 | 1998-03-03 | Hitachi Medical Corp | Magnetic resonance imaging apparatus |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6150257U (en) * | 1985-03-11 | 1986-04-04 | ||
| JPS63286142A (en) * | 1987-05-19 | 1988-11-22 | Toshiba Corp | Magnetic resonance imaging apparatus |
-
1992
- 1992-09-04 JP JP4237003A patent/JP2759185B2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6150257U (en) * | 1985-03-11 | 1986-04-04 | ||
| JPS63286142A (en) * | 1987-05-19 | 1988-11-22 | Toshiba Corp | Magnetic resonance imaging apparatus |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0691548A1 (en) | 1994-07-08 | 1996-01-10 | Sumitomo Special Metals Company Limited | Magnetic field generating device for use in MRI |
| JPH08140958A (en) * | 1994-11-25 | 1996-06-04 | Hitachi Medical Corp | Magnetic resonance imaging apparatus |
| US6236210B1 (en) | 1994-11-25 | 2001-05-22 | Hitachi Medical Corp. | Magnetic resonance imaging system |
| US6218837B1 (en) | 1994-11-25 | 2001-04-17 | Hitachi Medical Corporation | Magnetic resonance imaging system |
| US6215308B1 (en) | 1994-11-25 | 2001-04-10 | Hitachi Medical Corp. | Magnetic resonance imaging system |
| US6049208A (en) * | 1994-11-25 | 2000-04-11 | Hitachi Medical Corporation | Open type magnetic resonance imaging system which allows for easy access to the patient being examined |
| US5963117A (en) * | 1995-08-28 | 1999-10-05 | Shin-Etsu Chemical Co., Ltd. | Opposed magnet-type magnetic circuit assembly with permanent magnets |
| EP0985934A1 (en) * | 1995-08-28 | 2000-03-15 | Shin-Etsu Chemical Co., Ltd. | Opposed magnet-type magnetic circuit assembly with permanent magnets |
| EP0760484A3 (en) * | 1995-08-28 | 1997-07-23 | Shinetsu Chemical Co | Opposed magnet-type magnetic circuit assembly with permanent magnets |
| EP0760484A2 (en) * | 1995-08-28 | 1997-03-05 | Shin-Etsu Chemical Co., Ltd. | Opposed magnet-type magnetic circuit assembly with permanent magnets |
| EP1515150A1 (en) * | 1995-08-28 | 2005-03-16 | Shin-Etsu Chemical Co., Ltd. | Opposed magnet-type magnetic circuit assembly with permanent magnets |
| JPH09190913A (en) * | 1996-01-10 | 1997-07-22 | Hitachi Medical Corp | Superconducting magnet device and magnetic resonance imaging apparatus using this device |
| JPH1057345A (en) * | 1997-07-11 | 1998-03-03 | Hitachi Medical Corp | Magnetic resonance imaging apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2759185B2 (en) | 1998-05-28 |
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