JP2001095774A5 - - Google Patents
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- JP2001095774A5 JP2001095774A5 JP1999280470A JP28047099A JP2001095774A5 JP 2001095774 A5 JP2001095774 A5 JP 2001095774A5 JP 1999280470 A JP1999280470 A JP 1999280470A JP 28047099 A JP28047099 A JP 28047099A JP 2001095774 A5 JP2001095774 A5 JP 2001095774A5
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- JP
- Japan
- Prior art keywords
- magnetic field
- magnetic resonance
- phase
- imaging apparatus
- center
- 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.)
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- 238000005259 measurement Methods 0.000 description 7
- 238000005481 NMR spectroscopy Methods 0.000 description 6
- 238000002595 magnetic resonance imaging Methods 0.000 description 6
- 230000003068 static Effects 0.000 description 6
- 238000001208 nuclear magnetic resonance pulse sequence Methods 0.000 description 4
- 230000005284 excitation Effects 0.000 description 2
Description
【特許請求の範囲】
【請求項1】
静磁場を発生する静磁場発生手段、前記静磁場中に置かれた被検体に対して、高周波電磁波を印加する送信手段、前記静磁場に磁場勾配を与える傾斜磁場発生手段、前記被検体から発生する核磁気共鳴信号を計測する受信手段、これら送信手段、傾斜磁場発生手段および受信手段を所定のパルスシーケンスに従い制御する制御手段、計測された核磁気共鳴共信号に基づいて画像処理を行う画像処理手段を備えた磁気共鳴イメージング装置において、
前記制御手段は、前記静磁場の中心に対する計測領域中心のずれ量に応じて前記高周波磁場の位相および核磁気共鳴信号の計測位相を調整する手段を備えたことを特徴とする磁気共鳴イメージング装置。
【請求項2】
前記制御手段は、位相エンコード方向に発生する線状アーチファクトを前記計測領域に対し任意の位置に移動す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。
【請求項3】
前記画像処理手段は、計測領域の中心と前記静磁場の中心がずれた計測を行う際に、前記計測領域の中心を画像の中心にシフトし且つ前記線状アーチファクトを画像の端部に表示することを特徴とする請求項1または2に記載の磁気共鳴イメージング装置。
【請求項4】
前記所定のパルスシーケンスは、高周波磁場として励起パルスとそれに続く2以上の反転パルスを印加し、各反転パルス後に核磁気共鳴信号を計測するパルスシーケンスであり、前記制御手段は、前記励起パルスの位相および核磁気共鳴信号の計測位相を制御す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。
【請求項5】
前記制御手段は、前記所定のパルスシーケンスの繰り返し毎の位相エンコード量の変化に合わせて前記高周波磁場の位相および核磁気共鳴信号の計測位相を変化させることを特徴とする請求項1ないし4いずれか1項に記載の磁気共鳴イメージング装置。
[Claims]
[Claim 1]
Static magnetic field generating means for generating a static magnetic field, transmitting means for applying a high-frequency electromagnetic wave to a subject placed in the static magnetic field, gradient magnetic field generating means for giving a magnetic field gradient to the static magnetic field, and generating from the subject. A receiving means for measuring a nuclear magnetic resonance signal, a controlling means for controlling these transmitting means, a gradient magnetic field generating means and a receiving means according to a predetermined pulse sequence, and an image processing for performing image processing based on the measured nuclear magnetic resonance co-signal. In a magnetic resonance imaging apparatus equipped with means
The control means is a magnetic resonance imaging apparatus including means for adjusting the phase of the high frequency magnetic field and the measurement phase of a nuclear magnetic resonance signal according to the amount of deviation of the center of the measurement region with respect to the center of the static magnetic field.
2.
The magnetic resonance imaging apparatus according to claim 1, wherein the control means moves a linear artifact generated in the phase encoding direction to an arbitrary position with respect to the measurement region.
3.
The image processing means shifts the center of the measurement area to the center of the image and displays the linear artifact at the edge of the image when the center of the measurement area and the center of the static magnetic field are deviated from each other. The magnetic resonance imaging apparatus according to claim 1 or 2.
4.
The predetermined pulse sequence is a pulse sequence in which an excitation pulse followed by two or more inverting pulses are applied as a high-frequency magnetic field, and a nuclear magnetic resonance signal is measured after each inverting pulse, and the control means is a phase of the excitation pulse. The magnetic resonance imaging apparatus according to claim 1, wherein the measurement phase of the nuclear magnetic resonance signal is controlled.
5.
One of claims 1 to 4, wherein the control means changes the phase of the high-frequency magnetic field and the measurement phase of the nuclear magnetic resonance signal in accordance with a change in the phase encoding amount for each repetition of the predetermined pulse sequence. The magnetic resonance imaging apparatus according to item 1.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP28047099A JP4400957B2 (en) | 1999-09-30 | 1999-09-30 | Magnetic resonance imaging system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP28047099A JP4400957B2 (en) | 1999-09-30 | 1999-09-30 | Magnetic resonance imaging system |
Publications (3)
Publication Number | Publication Date |
---|---|
JP2001095774A JP2001095774A (en) | 2001-04-10 |
JP2001095774A5 true JP2001095774A5 (en) | 2006-10-26 |
JP4400957B2 JP4400957B2 (en) | 2010-01-20 |
Family
ID=17625531
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP28047099A Expired - Fee Related JP4400957B2 (en) | 1999-09-30 | 1999-09-30 | Magnetic resonance imaging system |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP4400957B2 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5000963B2 (en) * | 2006-09-29 | 2012-08-15 | 株式会社日立メディコ | Magnetic resonance imaging system |
-
1999
- 1999-09-30 JP JP28047099A patent/JP4400957B2/en not_active Expired - Fee Related
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