JPH03103233A - Magnetic resonance imaging device - Google Patents
Magnetic resonance imaging deviceInfo
- Publication number
- JPH03103233A JPH03103233A JP1241111A JP24111189A JPH03103233A JP H03103233 A JPH03103233 A JP H03103233A JP 1241111 A JP1241111 A JP 1241111A JP 24111189 A JP24111189 A JP 24111189A JP H03103233 A JPH03103233 A JP H03103233A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic field
- magnet
- coil
- magnetic resonance
- cooling fluid
- 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.)
- Pending
Links
- 238000002595 magnetic resonance imaging Methods 0.000 title claims description 10
- 239000012809 cooling fluid Substances 0.000 claims abstract description 18
- 230000003068 static effect Effects 0.000 claims abstract description 15
- 230000005284 excitation Effects 0.000 claims description 5
- 230000005855 radiation Effects 0.000 claims description 3
- 238000007789 sealing Methods 0.000 abstract description 7
- 238000010438 heat treatment Methods 0.000 abstract 2
- 230000020169 heat generation Effects 0.000 description 6
- 238000007599 discharging Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical group C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000003745 diagnosis Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000035807 sensation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Magnetic Resonance Imaging Apparatus (AREA)
Abstract
Description
【発明の詳細な説明】
［発明の目的］
（産業上の利用分野）
本発明は磁気共鳴現象を利用して断層像等の画像情報を
得る磁気共鳴イメージング装置（以下ＭＨＩ装置という
）に関する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a magnetic resonance imaging apparatus (hereinafter referred to as an MHI apparatus) that obtains image information such as a tomographic image using magnetic resonance phenomena.
（従来の技術）
医用診断に用いられるＭＨＩ装置は一様な静磁場に傾斜
磁場および励起回転磁場をｆｆｉ畳して磁気共鳴現象を
生じさせ、静磁場下に置かれた被検者より検出される磁
気共鳴信号を信号処理することによって断層像等の画像
情報を得るものであり、一般に静磁場を発生する円筒状
のマグネットと、このマグネット内に配置された傾斜磁
場コイルおよび前述した回転励起磁場を発生し且つ磁気
共鳴信号を受信するための送受信コイルなどから構戊さ
れる。(Prior Art) An MHI device used for medical diagnosis generates a magnetic resonance phenomenon by multiplying a uniform static magnetic field with a gradient magnetic field and an excitation rotating magnetic field, which is detected by a subject placed under a static magnetic field. Image information such as tomograms is obtained by signal processing the magnetic resonance signals generated by the magnet, and generally consists of a cylindrical magnet that generates a static magnetic field, a gradient magnetic field coil placed inside the magnet, and the aforementioned rotating excitation magnetic field. It consists of transmitting and receiving coils for generating magnetic resonance signals and receiving magnetic resonance signals.
（発明が解決しようとする課題）
このようなＭＲＩ装置の傾斜磁場コイルは、コイルに流
れる電流と静磁場との間に作用する電磁力により電流に
対応した変形力を受け、かつ上記電流が時間的に変化す
るため変形力によって振動を生じる。そして、この振動
によって騒音が発生すると共に傾斜磁場コイルに流れる
電流と導体との抵抗により熱が発生し、静磁場下に置か
れた被検者に不快感を与えるという問題があった。(Problem to be Solved by the Invention) The gradient magnetic field coil of such an MRI apparatus is subjected to a deforming force corresponding to the current due to the electromagnetic force acting between the current flowing in the coil and the static magnetic field, and the current is The deformation force causes vibrations. This vibration generates noise, and heat is generated due to the resistance between the current flowing through the gradient magnetic field coil and the conductor, which causes discomfort to the subject placed under the static magnetic field.
本発明はこのような問題点に着目してなされたもので、
静磁場下に置かれたの被検者に騒音、発熱等の不快感を
与えることのないＭＨＩ装置を提供することを目的とす
る。The present invention was made by focusing on these problems.
An object of the present invention is to provide an MHI device that does not cause unpleasant sensations such as noise and heat generation to a subject placed under a static magnetic field.
［発明の構成］
（課題を解決するための手段）
上記目的を達成するために本発明は、一様な静磁場を発
生する円筒状のマグネットと、このマグネット内に配置
され静磁場に対し傾斜した磁場を発生する傾斜磁場コイ
ルと、前記静磁場中に励起回転磁場を発生する送信コイ
ルと、これら送信コイル，傾斜磁場コイル及びマグネッ
トより発生する３つの磁場の磁気共鳴信号を受信する受
信コイルとを有する磁気共鳴イメージング装置において
、前記マグネット内に前記傾斜磁場コイルを収納する密
閉空間を形成し、この密閉空間内に冷却用流体を供給し
かつ排出する冷却流体給排手段を設けたものである。[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above object, the present invention includes a cylindrical magnet that generates a uniform static magnetic field, and a cylindrical magnet that is arranged within the magnet and is inclined with respect to the static magnetic field. a gradient magnetic field coil that generates a magnetic field; a transmitting coil that generates an excitation rotating magnetic field in the static magnetic field; and a receiving coil that receives magnetic resonance signals of three magnetic fields generated by the transmitting coil, the gradient magnetic field coil, and the magnet. A magnetic resonance imaging apparatus having a magnetic resonance imaging apparatus, wherein a sealed space for accommodating the gradient magnetic field coil is formed within the magnet, and a cooling fluid supply/discharge means is provided for supplying and discharging cooling fluid into the sealed space. .
（作 用）
すなわち、本発明は傾斜磁場コイルをマグネットの内側
に形成された密閉空間内に収納することにより、傾斜磁
場コイルの振動によって発生する騙音が被検者に伝わり
難くなり、ＭＨＩ装置の遮音性を高めることができる．
また、密閉空間内に冷却用流体を供給することにより、
密閉空間内に収納された傾斜磁場コイルを冷却用流体に
よって冷却することができ、傾斜磁場コイルの発熱を抑
制することができる。(Function) That is, by housing the gradient magnetic field coil in a closed space formed inside the magnet, the deceptive sound generated by the vibration of the gradient magnetic field coil is difficult to be transmitted to the subject, and the MHI device It is possible to improve the sound insulation properties of
In addition, by supplying cooling fluid into a closed space,
The gradient magnetic field coil housed in the closed space can be cooled by the cooling fluid, and heat generation of the gradient magnetic field coil can be suppressed.
（実施例） 以下、図面を参照して本発明の実施例を説明する。(Example) Embodiments of the present invention will be described below with reference to the drawings.
第１図ないし第３図は本発明の一実施例を示し、第１図
はＭＨＩ装置の正面図で、第２図は第１図の■−■線に
沿った矢視断面図である。第１図及び第２図において、
１は一様な静磁場を発生する円筒状のマグネットであり
、このマグネット１の内側には傾斜磁場コイル２を収納
するための密閉空間３が形成されている。この密閉空間
３はマグネット１内に同軸に配置された外側パイプ４と
、この外側パイプ４の内側に同軸に配置された内側バイ
プ５と、これら外側パイプ４及び内側パイプ５の両端に
設けられた封止リング６，７とから形成されており、封
止リング６．７には密閉空間３内に空気．水等の冷却用
流体を供給しかつ排出するための冷却流体供給配管８と
冷却流体排出配管９が接続されている。そして、上記冷
却流体供給配管８にはポンプ１０が接続され、このポン
プ１０により冷却用流体を密閉空間３内に供給する構造
となっている。1 to 3 show one embodiment of the present invention, in which FIG. 1 is a front view of the MHI device, and FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG. 1. In Figures 1 and 2,
Reference numeral 1 denotes a cylindrical magnet that generates a uniform static magnetic field, and a closed space 3 for accommodating a gradient magnetic field coil 2 is formed inside this magnet 1. This sealed space 3 includes an outer pipe 4 arranged coaxially within the magnet 1, an inner pipe 5 arranged coaxially inside the outer pipe 4, and provided at both ends of the outer pipe 4 and the inner pipe 5. It is formed of sealing rings 6, 7, and the sealing rings 6, 7 contain air within the sealed space 3. A cooling fluid supply pipe 8 and a cooling fluid discharge pipe 9 for supplying and discharging cooling fluid such as water are connected. A pump 10 is connected to the cooling fluid supply pipe 8, and the pump 10 supplies cooling fluid into the closed space 3.
また、前記密閉空間３内には励起回転磁場を発生するた
めの送信コイル１１と磁気共鳴信号を受信するための受
信コイル１２が収納されており、これらの送信コイル１
１及び受信コイル１２は内側パイプ５を巻き芯としてそ
のの外周に巻回装着されている。Further, a transmitting coil 11 for generating an excitation rotating magnetic field and a receiving coil 12 for receiving magnetic resonance signals are housed in the sealed space 3, and these transmitting coils 1
1 and the receiving coil 12 are wound around the inner pipe 5 as a winding core.
なお、前記内側バイプ５はマグネット１の端部にいくに
従って径が拡がっており、被検者に対し圧迫感を与えな
い構造となっている。また、前記外側パイプ４及び内側
バイプ５と封止リング６，７とは第３図に示すようにボ
ルト１３による結合構造となっており、外側バイプ４は
金具１４を介して静磁場コイル１にねじ止めされている
。The diameter of the inner pipe 5 increases toward the end of the magnet 1, so that it does not give a feeling of pressure to the subject. The outer pipe 4, the inner pipe 5, and the sealing rings 6, 7 are connected to each other by bolts 13 as shown in FIG. It is screwed on.
このような構成によると、傾斜磁場コイル２はマグネッ
ト１の内側に形成された密閉空間３内に収納されている
ため、傾斜磁場コイル２の振動によって発生する騒音が
被検者に伝わり難くなり、ＭＨＩ装置の遮音性を高める
ことができる。また、密閉空間３内に冷却用流体を供給
することにより、密閉空間３内に収納された傾斜磁場コ
イル２を冷却用流体によって冷却することができ、傾斜
磁場コイル２の発熱を抑えることができる。したがって
、本実施例においては傾斜磁場コイル２の発熱を抑制で
きると共に傾斜磁場コイル２の振動によって発生する騒
音が被検者に伝わり難くなり、これまで被検者に与えて
いた騒音や発熱による不快感を除去することができる。According to such a configuration, since the gradient magnetic field coil 2 is housed in the sealed space 3 formed inside the magnet 1, the noise generated by the vibration of the gradient magnetic field coil 2 is difficult to be transmitted to the subject. The sound insulation properties of the MHI device can be improved. Furthermore, by supplying the cooling fluid into the sealed space 3, the gradient magnetic field coil 2 housed in the sealed space 3 can be cooled by the cooling fluid, and heat generation of the gradient magnetic field coil 2 can be suppressed. . Therefore, in this embodiment, the heat generation of the gradient magnetic field coil 2 can be suppressed, and the noise generated by the vibration of the gradient magnetic field coil 2 is less likely to be transmitted to the subject, and the noise and heat generated by the subject have hitherto been affected. Pleasure can be removed.
また、上記実施例では送信コイル１１及び受信コイル１
２を内側パイプ５の外周に巻装し、たので、ＭＨＩ装置
の架台部の構造を簡単なものにすることができる。さら
に、内側バイプ５の径を端部にいくほど拡げたので、被
検者に対し圧迫感を与えることもない。Further, in the above embodiment, the transmitting coil 11 and the receiving coil 1
2 is wrapped around the outer periphery of the inner pipe 5, so that the structure of the pedestal part of the MHI device can be simplified. Furthermore, since the diameter of the inner pipe 5 is increased toward the end, it does not give a feeling of pressure to the subject.
なお、本発明は上記実施例に限定されるものではない。Note that the present invention is not limited to the above embodiments.
たとえば傾斜磁場コイル２の表面に放熱フィンを設ける
ことにより、傾斜磁場コイル２をより効果的に冷却する
ことができる。また、送信コイル１１及び受信コイル１
２を１つのコイルで共用するようにしてもよく、本発明
の要旨を逸脱しない範囲で種々の変形実施が可能である
。For example, by providing radiation fins on the surface of the gradient magnetic field coil 2, the gradient magnetic field coil 2 can be cooled more effectively. In addition, the transmitting coil 11 and the receiving coil 1
2 may be shared by one coil, and various modifications can be made without departing from the gist of the present invention.
［発明の効果］
以上説明したように請求項１記載の本発明によれば、傾
斜磁場コイルの発熱を抑制できると共に傾斜磁場コイル
の振動によって発生する騒音を低減でき、被検者に対し
騒音、発熱等の不快感を与えることのないＭＨＩ装置を
提供できる。[Effects of the Invention] As described above, according to the present invention as set forth in claim 1, it is possible to suppress the heat generation of the gradient magnetic field coils, and to reduce the noise generated by the vibrations of the gradient magnetic field coils, thereby reducing noise and noise to the subject. It is possible to provide an MHI device that does not cause discomfort such as heat generation.
また、請求項２記載の本発明によれば、密閉空間をマグ
ネット内に同軸に配置された外側パイプと、この外側パ
イプの内側に同軸に配置された内側パイプと、これら外
側パイプ及び内側パイプの両端に設けられた封止リング
とから形成することにより、内側パイプを送信コイル及
び受信コイルの巻き芯として利用することができ、ＭＨ
Ｉ装置の架台部の構造を簡素化することができる。Further, according to the present invention as set forth in claim 2, the sealed space is defined by an outer pipe disposed coaxially within the magnet, an inner pipe disposed coaxially inside the outer pipe, and the outer pipe and the inner pipe. By forming sealing rings provided at both ends, the inner pipe can be used as the winding core of the transmitting coil and receiving coil, and the MH
The structure of the pedestal part of the I device can be simplified.
また、請求項３記載の本発明によれば、内側パイプの内
径を端部にいくほど拡げることにより、被検者に圧迫感
を与えない構造とすることができる。Further, according to the third aspect of the present invention, by increasing the inner diameter of the inner pipe toward the end, it is possible to create a structure that does not give a feeling of pressure to the subject.
さらに、請求項４記載の本発明によれば、傾斜磁場コイ
ルの表面に放熱フィンを設けることにより、傾斜磁場コ
イルの冷却効果をさらに高めることができる。Furthermore, according to the fourth aspect of the present invention, by providing radiation fins on the surface of the gradient magnetic field coil, the cooling effect of the gradient magnetic field coil can be further enhanced.
第１図ないし第３図は本発明の一実施例を示し、第１図
はＭＨＩ装置のマグネットの正面図、第２図は第１図の
■一■線に沿った矢視断面図、第３図は第２図のＡ部を
示す詳細図である。
１・・・マグネット、２・・・傾斜磁場コイル、３・・
・密閉空間、４・・・外側パイプ、５・・・内側パイプ
、６，７・・・封止リング、８・・・冷却流体供給配管
、９・・・冷却流体排出配管、１０・・・ボンブ、１１
・・・送信コイル、１２・・・受信コイル。
Ｘ］
第１図1 to 3 show one embodiment of the present invention, in which FIG. 1 is a front view of the magnet of the MHI device, FIG. 2 is a sectional view taken along the line FIG. 3 is a detailed view showing section A in FIG. 2. 1... Magnet, 2... Gradient magnetic field coil, 3...
- Sealed space, 4... Outer pipe, 5... Inner pipe, 6, 7... Sealing ring, 8... Cooling fluid supply piping, 9... Cooling fluid discharge piping, 10... Bomb, 11
...Transmission coil, 12...Reception coil. X] Figure 1
Claims (4)
このマグネット内に配置され静磁場に対し傾斜した磁場
を発生する傾斜磁場コイルと、前記静磁場中に励起回転
磁場を発生する送信コイルと、これら送信コイル、傾斜
磁場コイル及びマグネットより発生する３つの磁場の磁
気共鳴信号を受信する受信コイルとを有する磁気共鳴イ
メージング装置において、前記マグネット内に前記傾斜
磁場コイルを収納する密閉空間を形成し、この密閉空間
内に冷却用流体を供給しかつ排出する冷却流体給排手段
を設けたことを特徴とする磁気共鳴イメージング装置。(1) A cylindrical magnet that generates a uniform static magnetic field,
A gradient magnetic field coil that is placed inside the magnet and generates a magnetic field tilted with respect to the static magnetic field, a transmitting coil that generates an excitation rotating magnetic field in the static magnetic field, and three In a magnetic resonance imaging apparatus having a receiving coil for receiving a magnetic resonance signal of a magnetic field, a sealed space is formed in the magnet to house the gradient magnetic field coil, and a cooling fluid is supplied and discharged into the sealed space. A magnetic resonance imaging apparatus characterized in that a cooling fluid supply/discharge means is provided.
された外側パイプと、この外側パイプの内側に同軸に配
置された内側パイプと、これら外側パイプ及び内側パイ
プの両端に設けられた封止リングとから形成され、前記
内側パイプの外周には前記送信コイルおよび受信コイル
が装着されていることを特徴とする請求項１記載の磁気
共鳴イメージング装置。(2) The sealed space includes an outer pipe disposed coaxially within the magnet, an inner pipe coaxially disposed inside the outer pipe, and seals provided at both ends of the outer pipe and the inner pipe. 2. The magnetic resonance imaging apparatus according to claim 1, wherein the inner pipe is formed of a ring, and the transmitting coil and the receiving coil are attached to the outer periphery of the inner pipe.
にしたがって内径が拡がっていることを特徴とする請求
項２記載の磁気共鳴イメージング装置。(3) The magnetic resonance imaging apparatus according to claim 2, wherein the inner pipe has an inner diameter that increases toward an end of the magnet.
設けられていることを特徴とする請求項１記載の磁気共
鳴イメージング装置。(4) The magnetic resonance imaging apparatus according to claim 1, wherein the gradient magnetic field coil is provided with radiation fins on its surface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1241111A JPH03103233A (en) | 1989-09-18 | 1989-09-18 | Magnetic resonance imaging device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1241111A JPH03103233A (en) | 1989-09-18 | 1989-09-18 | Magnetic resonance imaging device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03103233A true JPH03103233A (en) | 1991-04-30 |
Family
ID=17069450
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1241111A Pending JPH03103233A (en) | 1989-09-18 | 1989-09-18 | Magnetic resonance imaging device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03103233A (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06223476A (en) * | 1993-01-27 | 1994-08-12 | Sony Corp | Recording and reproducing device |
| JPH0880289A (en) * | 1994-09-12 | 1996-03-26 | Ge Yokogawa Medical Syst Ltd | Cooling structure for mr device coil |
| JPH0898829A (en) * | 1994-09-30 | 1996-04-16 | Shimadzu Corp | Magnetic resonance tomographic system |
| JPH09510A (en) * | 1995-06-23 | 1997-01-07 | Ge Yokogawa Medical Syst Ltd | Coil mechanism of magnetic resonance photographing device |
| JP2003033330A (en) * | 2001-07-09 | 2003-02-04 | Ge Medical Systems Global Technology Co Llc | Rf-signal receiving device and magnetic resonance imaging device |
| JP2005144165A (en) * | 2003-11-05 | 2005-06-09 | Ge Medical Systems Global Technology Co Llc | Heat management apparatus and use of the same |
| JP2008012296A (en) * | 2006-06-30 | 2008-01-24 | General Electric Co <Ge> | Apparatus and method for providing forced airflow to surface of gradient coil |
| EP2237059A1 (en) * | 2009-03-31 | 2010-10-06 | General Electric Company | Cooled gradient coil system |
| US20150192650A1 (en) * | 2014-01-09 | 2015-07-09 | Kabushiki Kaisha Toshiba | Magnetic resonance imaging apparatus |
| JP2018198938A (en) * | 2018-07-04 | 2018-12-20 | キヤノンメディカルシステムズ株式会社 | Magnetic resonance imaging device |
-
1989
- 1989-09-18 JP JP1241111A patent/JPH03103233A/en active Pending
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06223476A (en) * | 1993-01-27 | 1994-08-12 | Sony Corp | Recording and reproducing device |
| JPH0880289A (en) * | 1994-09-12 | 1996-03-26 | Ge Yokogawa Medical Syst Ltd | Cooling structure for mr device coil |
| JPH0898829A (en) * | 1994-09-30 | 1996-04-16 | Shimadzu Corp | Magnetic resonance tomographic system |
| JPH09510A (en) * | 1995-06-23 | 1997-01-07 | Ge Yokogawa Medical Syst Ltd | Coil mechanism of magnetic resonance photographing device |
| JP2003033330A (en) * | 2001-07-09 | 2003-02-04 | Ge Medical Systems Global Technology Co Llc | Rf-signal receiving device and magnetic resonance imaging device |
| JP2005144165A (en) * | 2003-11-05 | 2005-06-09 | Ge Medical Systems Global Technology Co Llc | Heat management apparatus and use of the same |
| JP2008012296A (en) * | 2006-06-30 | 2008-01-24 | General Electric Co <Ge> | Apparatus and method for providing forced airflow to surface of gradient coil |
| EP2237059A1 (en) * | 2009-03-31 | 2010-10-06 | General Electric Company | Cooled gradient coil system |
| CN101852842A (en) * | 2009-03-31 | 2010-10-06 | 通用电气公司 | Cooled gradient coil system |
| US8063638B2 (en) | 2009-03-31 | 2011-11-22 | General Electric Company | Liquid dielectric gradient coil system and method |
| US20150192650A1 (en) * | 2014-01-09 | 2015-07-09 | Kabushiki Kaisha Toshiba | Magnetic resonance imaging apparatus |
| JP2015130918A (en) * | 2014-01-09 | 2015-07-23 | 株式会社東芝 | magnetic resonance imaging apparatus |
| US10962612B2 (en) | 2014-01-09 | 2021-03-30 | Toshiba Medical Systems Corporation | Magnetic resonance imaging apparatus having high frequency coil isolated from gradient coils and a tapered / inclined coil support unit |
| JP2018198938A (en) * | 2018-07-04 | 2018-12-20 | キヤノンメディカルシステムズ株式会社 | Magnetic resonance imaging device |
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