JPS6195237A - Nuclear magnetic resonance computer diagnostic photography apparatus - Google Patents

Nuclear magnetic resonance computer diagnostic photography apparatus

Info

Publication number
JPS6195237A
JPS6195237A JP59215187A JP21518784A JPS6195237A JP S6195237 A JPS6195237 A JP S6195237A JP 59215187 A JP59215187 A JP 59215187A JP 21518784 A JP21518784 A JP 21518784A JP S6195237 A JPS6195237 A JP S6195237A
Authority
JP
Japan
Prior art keywords
power
coil
magnetic field
power source
magnetic resonance
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
Application number
JP59215187A
Other languages
Japanese (ja)
Inventor
Isamu Uetomi
上冨　勇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Priority to JP59215187A priority Critical patent/JPS6195237A/en
Publication of JPS6195237A publication Critical patent/JPS6195237A/en
Pending legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
    • G01R33/32—Excitation or detection systems, e.g. using radio frequency signals
    • G01R33/36—Electrical details, e.g. matching or coupling of the coil to the receiver
    • G01R33/3628—Tuning/matching of the transmit/receive coil

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  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Magnetic Resonance Imaging Apparatus (AREA)

Abstract

PURPOSE:To form a correct RF magnetic field even if the load state of a RF coil changes, by providing an automatic preset circuit and matching the output of a RF power source with predetermined RF power. CONSTITUTION:When an object to be examined is inserted, the operation point of a RF coil 3 transfers to a curve B(f1.p2) from a curve A(f1.p1). This RF magnetic field is monitored by the search coil 4 in an automatic preset circuit 10 and DC voltage proportional to a RF magnetic field is outputted by a detection amplifying circuit 5 to be inputted to a RF power source (1A) while a presetting circuit 6 outputs the preset level corresponding to the image pick-up mode of the object to be examined. The DC voltage of the RF magnetic field is compared with the preset level by a RF power source (1A) to raise the output of RF power. If an automatic preset circuit 10, which forms a trial operation mode at every object to be examined and sets the same so as to preliminarily form the correct RF magnetic field in matching relation to a load state, is provided, an operation point is automatically set to a curve C(f1.p1).

Description

【発明の詳細な説明】 〔産業上の利用分野〕 この発明は、核磁気共鳴コンピュータ診断撮像装置（ニ
ーＣＴ）　　におけるＲＦ’磁界例えば〜イク・波磁界
め安定化に関するものである。　　　□〔従来の技術〕
。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] This invention relates to the stabilization of RF' magnetic fields, such as ~-wave magnetic fields, in nuclear magnetic resonance computer diagnostic imaging systems (knee CT). □ [Conventional technology]
.

従来この種の装置として第り図忙示すものがあった。図
において、（１）はＲＦ電源例えばマイクロ波電源、（
コ）は共振整合回路、（Ｊ）はＲＦコイルである。第３
図は第４図におけるＲＦコイル（３）の供給電力・周波
数特性を示すもので、ＰはＲＦコイル（，７１への供給
電力、ｆはＲＦ周波数−線ＡはＲＦコイル（Ｊ）内に被
検体（図示しない）例えば人体などが挿入されていない
ときの特性つまり無負荷時の供給電力・周波数特性１曲
線Ｂは被検体が挿入された負荷時の供給電力・周波数特
性を示す。ｆ。Conventionally, there have been several types of devices of this type. In the figure, (1) is an RF power source, such as a microwave power source, (
C) is a resonant matching circuit, and (J) is an RF coil. Third
The figure shows the power supply/frequency characteristics of the RF coil (3) in Figure 4, where P is the power supplied to the RF coil (, 71, f is the RF frequency, and line A is the power applied to the RF coil (J). Characteristics when a specimen (not shown), for example, a human body, etc., is not inserted, that is, supplied power and frequency characteristics at no load.1 Curve B shows the supplied power and frequency characteristics when a specimen is inserted and loaded.f.

は無負荷時の共振周波数、ｆｔは選ばれたＮＭＲＦＣＴ
の動作周波！？！ｉ（これは直流磁界強度で一義的に決
まる）、ｐｌは無負荷時の周波数ｆｚにおけるＲＦコイ
ル（３）への供給電力、ｐコは負荷時の周波数ｆ／にお
けるＲＦコイル（３）への供給電力、ｆｌは負荷時の共
振周波数である。is the no-load resonant frequency, ft is the selected NMRFCT
Operating frequency! ? ! i (this is uniquely determined by the DC magnetic field strength), pl is the power supplied to the RF coil (3) at frequency fz when no load is applied, and pco is the power supplied to the RF coil (3) at frequency f/ when loaded. The supplied power, fl, is the resonant frequency under load.

次に動作について説明する。ＲＦコイル（３）はインダ
クタンスと抵抗とからなるインピーダンスｚ＝Ｒ＋Ｊｘ
を持つ。このＲＦコイル（，７）に電力（電流）を供給
して内部にＲＦ磁界を形成する。しかしＲＦ電源（１）
から効率良（ＲＦコイル（３）に電力を供給するために
は、共振整合回路２）でＲＦコイル（３）のインダクタ
ンスとの共振状態を形成し、ＲＦ電源（１）より児だ共
振整合回路側のインピーダンスを抵抗にし〔つまり容量
などを用ちいてＲＦコイル（Ｊｌのインダクタンスを打
ち消す］かつＲＦ　電源（１）の内部抵抗と等しくする
ことが必要となる。Next, the operation will be explained. The RF coil (3) has impedance z=R+Jx consisting of inductance and resistance.
have. Power (current) is supplied to this RF coil (, 7) to form an RF magnetic field inside. But RF power supply (1)
In order to efficiently supply power to the RF coil (3), a resonant state is formed with the inductance of the RF coil (3) in the resonant matching circuit 2), and the resonant matching circuit is connected to the RF power source (1). It is necessary to make the side impedance a resistance (that is, use a capacitor or the like to cancel the inductance of the RF coil (Jl)) and make it equal to the internal resistance of the RF power source (1).

第Ｓ図の曲ｉＡは第弘図の回路構成における無負荷動作
状態を示し、ｆＯけ共振周波数、ｆｚは動作周波数であ
り、このときはＲＦ’電源（／ｌとの整合がとれていて
、ＲＦコイル（３）へは電力ｐｌを供給できることにな
る。この曲線Ａを見ただけではＲＦコイル（Ｊ）へｐｌ
より大きい電力を供給できるように見受けられるが、Ｒ
Ｆ電源（１）との整合性がくずれるので、′ａ力の供給
は必ずしも改善されない。Curve iA in Fig. S shows the no-load operating state in the circuit configuration shown in Fig. H, where fO is the resonant frequency and fz is the operating frequency. This means that power pl can be supplied to the RF coil (3).Just by looking at this curve A, it is possible to supply pl to the RF coil (J).
Although it appears to be able to supply more power, R
Since the compatibility with the F power supply (1) is lost, the supply of 'a force is not necessarily improved.

曲線Ｂは被検体をＲＦコイル（、？）に挿入して負荷状
態にしたときのＲＦコイル（３）への供給電力・周波数
特性を示す。インダクタンスが小さくなり抵抗損失が増
えるため０曲線が急峻でなくなり、共振周波数も高い方
の１２にずれる。従って、動作周波数カにおける供給電
力はｐａＫ減少することになる。つまり、動作周波数で
／でＲＦコイル（３）の負荷状態が変化すれば、ＲＦ′
：１イル（３）への供給電力が変化し、従って内部に形
成されるＲＦ磁界が変化することが分る。Curve B shows the power and frequency characteristics supplied to the RF coil (3) when a subject is inserted into the RF coil (?) and the RF coil (?) is in a loaded state. As the inductance decreases and resistance loss increases, the 0 curve becomes less steep, and the resonant frequency shifts to the higher 12. Therefore, the supplied power at the operating frequency is reduced by paK. In other words, if the load condition of the RF coil (3) changes at/at the operating frequency, RF'
It can be seen that the power supplied to the 1-il (3) changes, and therefore the RF magnetic field formed inside changes.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

従来のＮＭＲＦＣＴは以上のように構成されていたので
、ＲＦコイルの負荷状態（被検体としての人体の頭部、
全身、子供、大人など）に応じてＲＦコイルの形成する
ＲＦ磁界が変化し、被検体によって毎回共振整合回路の
同調を取り直すなどの問題点があった。Since the conventional NMRFCT was configured as described above, the load condition of the RF coil (the head of the human body as the subject,
The RF magnetic field formed by the RF coil changes depending on the subject (whole body, child, adult, etc.), and there are problems in that the resonant matching circuit is retuned each time depending on the subject.

この発明はこのような問題点をなく丁ためになされたも
ので、たとえＲＦコイルの負荷状態が変っても共振整合
回路の同調を取り直す必要のない安定なＮＭＲＦＣＴを
得ることを目的とする。The present invention has been made to eliminate these problems, and aims to provide a stable NMRFCT that does not require retuning of the resonant matching circuit even if the load condition of the RF coil changes.

〔問題点を解決するための手段〕[Means for solving problems]

この発明に係るＮＭＲＦＣＴは、ＲＦ＠力またはＲＦｓ
界をモニタする手段と、このモニタ手段のモニタ信号な
ＲＦ電源へフィードバックする手段と、ＲＦ電源に所定
のＲＦ電力をプリセットするプリセット器とから成る自
動プリセット回路を投げたものである。The NMRFCT according to this invention is based on RF@force or RFs.
The automatic presetting circuit includes a means for monitoring the field, a means for feeding back a monitor signal of the monitoring means to the RF power supply, and a presetting device for presetting the RF power to a predetermined RF power.

〔作　用〕[For production]

この発明においては、自動プリセット回路が所定のＲＦ
電力ＫＲＦ電源の出力を合わせるので。In this invention, the automatic preset circuit
Because it matches the output of the power KRF power supply.

たとえＲＦコイルの負荷状態が変っても、共Ｓ整合回路
の同調を取り直す必要がない。Even if the load condition of the RF coil changes, there is no need to retune the co-S matching circuit.

〔実施例〕〔Example〕

以下、この発明の一実施例を図について説明する第１図
はこの発明の一実施例を示すブロック図二タ手段例えば
ＲＦコイル＜３）の形成するＲＦａ界をモニタする制御
サーチコイル、（よ）はこのサーチコイル（３）のモニ
タ信号なＲＦ電源（／Ａ）へフィードバックする手段例
えば検波・増幅回路、（Ａ）はＲＦ電源（／Ａ）に所定
のＲＦ電力をプリセットするプリセット器である。なお
、これらのサーチコイル（り）、検波・増幅回路（５）
およびプリセット器（６）は自動プリセット回路（１０
）を構成する６第λ図はＮＭＲＦＣＴの撮像モードのシ
ーケンスΦノ（ターンを示す図で、５Ｑｚ−８Ｑｎ　は
被検体に応じて決められる傾斜砒界、スライス磁界、Ｒ
Ｆ）くルスなどの時系列的なパターンを、示しＢＱｏは
この発明にかかわる試し運転モードのパターンである第
３図は第５図に示したｍ、Ｆコイルの供給電力１周波数
特性に曲線Ｃを加えたもので、この曲線Ｃは曲線Ｂを周
波数ｆｌにおいて供給電力ｐ、になるように移動させた
ものであり、こ４の移動はＲＦ電源の出力を上げること
によって出来る。Hereinafter, an embodiment of the present invention will be explained with reference to the drawings. Fig. 1 is a block diagram showing an embodiment of the present invention. ) is a means for feeding back the monitor signal of this search coil (3) to the RF power supply (/A), such as a detection/amplification circuit, and (A) is a preset device that presets the RF power supply (/A) to a predetermined RF power. . In addition, these search coils (ri), detection/amplification circuits (5)
And the preset device (6) is an automatic preset circuit (10
) is a diagram showing the sequence Φ (turn) of the imaging mode of NMRFCT, where 5Qz-8Qn are the gradient arsenic field, slice magnetic field, and
BQo is the pattern of the test run mode related to this invention. Figure 3 shows the curve C for the power supply power 1 frequency characteristic of the m and F coils shown in Figure 5. This curve C is obtained by shifting the curve B so that the supplied power becomes p at the frequency fl, and this shift can be made by increasing the output of the RF power source.

次にこの発明の動作について説明する。ＲＦ電源（／Ａ
ンの出力が一定とすると、ＲＦコイル（３）の動作点は
被検体を挿入することにより曲線人の点（ｆｔ、　ｐｌ
）より曲線Ｂの点（ｒｚ、ｐコ）へと移る。Next, the operation of this invention will be explained. RF power supply (/A
Assuming that the output of the RF coil (3) is constant, the operating point of the RF coil (3) is changed to the curved point (ft, pl) by inserting the subject.
) to point (rz, pco) on curve B.

、＋　　　ｐｔ＞”ｘｆＫｆ）”’Ｑ、ＲＦ”４′（”
＞Ｆｉ’３１１ＣｔＢ＊；４　ＲＦａｉ　’界は弱くな
る。自動てリセット回路（１０）中のサーチコイル（り
）でこのＲＦ磁界をモニタし、検波・増幅回路（３）で
モニタ信号すなわちＲ’Ｆ磁界に比例した直流電圧を出
力してＲＦ電源（／Ａ）への入力とする一方、プリセッ
ト器（６）は被検体の撮像モードに応じたプリセット・
レベルを出力する。次にＲＦ電源（／Ａ）でＲＦ磁界の
直流電圧とＲＦ　ｚ力のプリセット・レベルとを比較し
て、プリセット・レベルまでＲＦ電力の出力を上げる。, + pt>"xfKf)"'Q, RF"4'("
>Fi'311CtB*;4 RFai' field becomes weaker. The search coil (RI) in the automatic reset circuit (10) monitors this RF magnetic field, and the detection/amplification circuit (3) outputs a monitor signal, that is, a DC voltage proportional to the R'F magnetic field, and the RF power supply (/ A), while the preset device (6) inputs the preset data according to the imaging mode of the subject.
Output the level. Next, the RF power supply (/A) compares the DC voltage of the RF magnetic field and the preset level of the RF z force, and increases the RF power output to the preset level.

従って、被検体毎に撮像モードの前に試し運転モードを
作り。Therefore, create a trial run mode for each subject before starting the imaging mode.

負荷の状態に合せて正しいＲＦ磁界を前もって作るよう
にセットする自動プリ七ット回路（１０）を設けると、
自動的に曲線Ｃの点（ｆｔ、ｐｔ）に動作点がセットさ
れることになる。If an automatic pre-set circuit (10) is provided to set the correct RF magnetic field in advance according to the load condition,
The operating point is automatically set at the point (ft, pt) of the curve C.

動作点（ｆｔ、ｐｔ）は必ずしもＲＦ’電源（／Ａと共
振整合回路（２）との整合がとれた状態ではなｌ、）。The operating point (ft, pt) is not necessarily the state where the RF' power supply (/A and the resonance matching circuit (2) are matched).

つまり、かなり大きなＶ８ＷＲが立つ場合もあることを
覚悟して、ＲＦ電源（／Ａ）を設計してお（必要がある
。In other words, it is necessary to design the RF power supply (/A) with the understanding that a fairly large V8WR may be required.

又、試し運動モード・パター′ン内のＲＦ電力のパター
ンは、パルスの繰返して゛あっても良０シ直流的な時間
幅の大きいパルスがあっても良（・。検　　、Ｐ被・増
幅回路（ｊ２）で、前）者の場合はサンプルφホールド
或はピーク・ホールド的な回路を更に組込むことで達成
できる。　　□ 以上のように、一つの動作点（ｆｔ・ｐｌ）が決定され
れば、同一被検体である限りＲＦコイルの負荷状態は同
じであるため、撮像モード・パターンによってｐｌを変
化させる必要のあるときはＲＦ電源（ｔＡ）の出力を下
げれば良い。これはＲＦ電源（／Ａ）の出力が変化する
のみで、共振整合回路（コ）やＲＦコイル（、？）との
整合状態は変化しない。つまり、プリセット器（６）に
マイクロプロセッサを組み込み、ｐｌの変化パターンの
ブ四グラム化（プリセット・パターンの記憶化）をする
のは容易であるし、又試し運転モードを非常に低い電力
で行なった後の撮像モードへの置替え（比例計算による
スケーリング）も可能である。In addition, the RF power pattern in the trial exercise mode pattern may have repeated pulses or DC-like pulses with a large time width. In (j2), the former case can be achieved by further incorporating a sample φ hold or peak hold type circuit. □ As mentioned above, once one operating point (ft/pl) is determined, the load condition of the RF coil remains the same as long as the same object is being examined, so it is necessary to change pl depending on the imaging mode/pattern. In such a case, the output of the RF power supply (tA) should be lowered. This only changes the output of the RF power supply (/A), but does not change the matching state with the resonance matching circuit (c) or the RF coil (?). In other words, it is easy to incorporate a microprocessor into the preset device (6) and convert the PL change pattern into a four-gram (memory of the preset pattern), and it is also possible to perform the test run mode using very low power. It is also possible to replace the imaging mode with a later imaging mode (scaling by proportional calculation).

変流器や変圧器によりモニタして、フィードバックする
ことも可能である。It is also possible to monitor and provide feedback using a current transformer or transformer.

〔発明の効果〕〔Effect of the invention〕

以上のように、この発明によれば、ＲＦコイル内に挿入
する被検体（負荷）が変わっても絶えず正しいＲＦａ界
が形成できるように自動プリセット回路を構成したので
、安定したＮＭＲＦＣＴを提供できる効果がある。As described above, according to the present invention, since the automatic preset circuit is configured so that a correct RFa field can be constantly formed even if the object (load) inserted into the RF coil changes, it is possible to provide stable NMRFCT. There is.

【図面の簡単な説明】[Brief explanation of the drawing]

ｇ／図はこの発明の一実施例を示すブロック図、　′第
コ図はこの発明の試し運転モードを加えた時系列的なパ
ターンを示す図、第３図はこの発明のＮ　Ｍ　Ｐ。 −ＣＴ　の供給電力・周波数特性を示す曲線図、Ｗ。 ダ図は従来のＮＭＲＦＣＴを示すブロック図、第３図は
従来のＮＭＲＦＣＴの供給電力・周波数特性を示す曲膀
図である。 ／Ａ”　”　ＲＦｍ＃、（２）−−共Ｆｉ　整合回路、
（，７１−−ＲＦコイル、　（＜’）・・サーチコイル
、　（、ｌｔ）・・検波。 増幅回路、（６）・・プリセット器。 なお、各図中、同一符号は同−又は相当部分を示す。 ＋ｏ：ｔｔｍｙ＋）ｔｖＦｃｙａ−％’　”熱２図 馬３図 烏４図 壓５図Figure g/ is a block diagram showing an embodiment of the present invention, Figure 1 is a diagram showing a time-series pattern including the trial run mode of the present invention, and Figure 3 is the NMP of the present invention. -Curve diagram showing power supply/frequency characteristics of CT, W. Fig. 3 is a block diagram showing a conventional NMRFCT, and Fig. 3 is a curved diagram showing power supply/frequency characteristics of the conventional NMRFCT. /A” ”RFm#, (2)--Co-Fi matching circuit,
(,71--RF coil, (<')...Search coil, (,lt)...Detection. Amplifier circuit, (6)...Preset device. In each figure, the same reference numerals are the same or equivalent parts. +o:ttmy+)tvFcya-%' ``Heat 2, Horse 3, Crow 4, He 5

Claims (6)

【特許請求の範囲】[Claims] （１）ＲＦ電源からのＲＦ電力が共振整合回路を通して
供給されることによりＲＦ磁界を形成するＲＦコイルを
備えた核磁気共鳴コンピユータ診断撮像装置において、
前記ＲＦ電力または前記ＲＦ磁界をモニタしかつこれを
前記ＲＦ電源へフイードバツクすることにより所定のＲ
Ｆ電力に前記ＲＦ電源の出力を合わせる自動プリセツト
回路を設けたことを特徴とする核磁気共鳴コンピユータ
診断撮像装置。(1) In a nuclear magnetic resonance computer diagnostic imaging device equipped with an RF coil that forms an RF magnetic field by supplying RF power from an RF power source through a resonant matching circuit,
A predetermined R is achieved by monitoring the RF power or the RF magnetic field and feeding it back to the RF power source.
A nuclear magnetic resonance computer diagnostic imaging apparatus characterized in that an automatic preset circuit is provided for adjusting the output of the RF power source to the F power. （２）自動プリセツト回路は、ＲＦ電源に所定のＲＦ電
力をプリセツトするプリセツト器を含む特許請求の範囲
第１項記載の核磁気共鳴コンピユータ診断撮像装置。(2) The nuclear magnetic resonance computer diagnostic imaging apparatus according to claim 1, wherein the automatic preset circuit includes a preset device that presets the RF power source to a predetermined RF power. （３）自動プリセツト回路は、ＲＦコイルの形成するＲ
Ｆ磁界をモニタする手段としてのサーチコイルを含む特
許請求の範囲第１項または第２項記載の核磁気共鳴コン
ピユータ診断撮像装置。(3) The automatic preset circuit uses R formed by the RF coil.
3. A nuclear magnetic resonance computer diagnostic imaging apparatus according to claim 1, which includes a search coil as means for monitoring the F magnetic field. （４）自動プリセツト回路は、ＲＦ電源からＲＦコイル
へ供給されるＲＦ電力をモニタする手段としての変流器
または変圧器を含む特許請求の範囲第１項または第２項
記載の核磁気共鳴コンピユータ診断撮像装置。(4) The nuclear magnetic resonance computer according to claim 1 or 2, wherein the automatic preset circuit includes a current transformer or a transformer as means for monitoring the RF power supplied from the RF power source to the RF coil. Diagnostic imaging device. （５）自動プリセツト回路は、モニタ手段のモニタ信号
をＲＦ電源へフイードバツクする手段としての検波・増
幅回路を含む特許請求の範囲第３項または第４項記載の
核磁気共鳴コンピユータ診断撮像装置。(5) The nuclear magnetic resonance computer diagnostic imaging apparatus according to claim 3 or 4, wherein the automatic preset circuit includes a detection/amplification circuit as means for feeding back the monitor signal of the monitor means to the RF power source. （６）プリセツト器は、マイクロプロセツサが組み込ま
れている特許請求の範囲第２項記載の核磁気共鳴コンピ
ユータ診断撮像装置。(6) The nuclear magnetic resonance computer diagnostic imaging apparatus according to claim 2, wherein the preset device incorporates a microprocessor.
JP59215187A 1984-10-16 1984-10-16 Nuclear magnetic resonance computer diagnostic photography apparatus Pending JPS6195237A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP59215187A JPS6195237A (en) 1984-10-16 1984-10-16 Nuclear magnetic resonance computer diagnostic photography apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP59215187A JPS6195237A (en) 1984-10-16 1984-10-16 Nuclear magnetic resonance computer diagnostic photography apparatus

Publications (1)

Publication Number Publication Date
JPS6195237A true JPS6195237A (en) 1986-05-14

Family

ID=16668114

Family Applications (1)

Application Number Title Priority Date Filing Date
JP59215187A Pending JPS6195237A (en) 1984-10-16 1984-10-16 Nuclear magnetic resonance computer diagnostic photography apparatus

Country Status (1)

Country Link
JP (1) JPS6195237A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1189071A2 (en) * 2000-09-19 2002-03-20 GE Medical Systems Global Technology Company LLC Method of driving an MRI rf transmitter coil
WO2002084317A1 (en) * 2001-04-11 2002-10-24 Koninklijke Philips Electronics Nv Rf transmit calibration for open mri systems
WO2012059845A1 (en) * 2010-11-02 2012-05-10 Koninklijke Philips Electronics N.V. Method of characterizing an rf transmit chain
JP2014528296A (en) * 2011-10-06 2014-10-27 シーメンス アクチエンゲゼルシヤフトＳｉｅｍｅｎｓ Ａｋｔｉｅｎｇｅｓｅｌｌｓｃｈａｆｔ Two-channel magnetic resonance tomography system
RU2574312C2 (en) * 2010-11-02 2016-02-10 Конинклейке Филипс Электроникс Н.В. Method of determining characteristics of radio-frequency transmitting circuit

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
A WHOLE-BODY NMR IMAGING MACHIVE=1980 *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1189071A2 (en) * 2000-09-19 2002-03-20 GE Medical Systems Global Technology Company LLC Method of driving an MRI rf transmitter coil
EP1189071A3 (en) * 2000-09-19 2004-07-14 GE Medical Systems Global Technology Company LLC Method of driving an MRI rf transmitter coil
WO2002084317A1 (en) * 2001-04-11 2002-10-24 Koninklijke Philips Electronics Nv Rf transmit calibration for open mri systems
US6552538B2 (en) 2001-04-11 2003-04-22 Koninklijke Philips Electronics, N.V. RF transmit calibration for open MRI systems
WO2012059845A1 (en) * 2010-11-02 2012-05-10 Koninklijke Philips Electronics N.V. Method of characterizing an rf transmit chain
CN103201644A (en) * 2010-11-02 2013-07-10 皇家飞利浦电子股份有限公司 Method of characterizing an RF transmit chain
RU2574312C2 (en) * 2010-11-02 2016-02-10 Конинклейке Филипс Электроникс Н.В. Method of determining characteristics of radio-frequency transmitting circuit
US9575146B2 (en) 2010-11-02 2017-02-21 Koninklijke Philips Electronics N.V. Method of characterizing
JP2014528296A (en) * 2011-10-06 2014-10-27 シーメンス アクチエンゲゼルシヤフトＳｉｅｍｅｎｓ Ａｋｔｉｅｎｇｅｓｅｌｌｓｃｈａｆｔ Two-channel magnetic resonance tomography system
US9784811B2 (en) 2011-10-06 2017-10-10 Siemens Aktiengesellschaft Two-channel magnetic resonance imaging

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